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Portland State University

1997

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Full-Text Articles in Engineering

Optimal Block Encoding And Optimal Entropy For Lossless Image Compression, Larry Ray Dennis Dec 1997

Optimal Block Encoding And Optimal Entropy For Lossless Image Compression, Larry Ray Dennis

Dissertations and Theses

In this thesis, a novel approach is designed using a quad-tree stack structure to encode the image to determine the optimal block size at the optimal and effective entropy in the lossless image compression method. Proof is given through encoding of the predictor and randomly constructed planes. There is a high degree of relationship between the placement of bits in the planes. Clearly results shows that use of the optimal entropy and encoding block sizes will increase the compression ratio using the lossless method. The cost of using the block size methods to encoding and entropy is discussed and proven. …


Sinusoidal-Gaussian Beams In Complex Optical Systems, Lee W. Casperson, Dennis G. Hall, Anthony A. Tovar Dec 1997

Sinusoidal-Gaussian Beams In Complex Optical Systems, Lee W. Casperson, Dennis G. Hall, Anthony A. Tovar

Electrical and Computer Engineering Faculty Publications and Presentations

Sinusoidal-Gaussian beam solutions are derived for the propagation of electromagnetic waves in free space and in media having at most quadratic transverse variations of the index of refraction and the gain or loss. The resulting expressions are also valid for propagation through other real and complex lens elements and systems that can be represented in terms of complex beam matrices. The solutions are in the form of sinusoidal functions of complex argument times a conventional Gaussian beam factor. In the limit of large Gaussian beam size, the sine and cosine factors of the beams are dominant and reduce to the …


Pressure Impulses During Microsecond Laser Ablation, Hanqun Shangguan, Lee W. Casperson, Scott A. Prahl Dec 1997

Pressure Impulses During Microsecond Laser Ablation, Hanqun Shangguan, Lee W. Casperson, Scott A. Prahl

Electrical and Computer Engineering Faculty Publications and Presentations

The collapse of laser-induced cavitation bubbles creates acoustic transients within the surrounding medium and also pressure impulses to the ablation target and light-delivery fiber during microsecond laser ablation. The impulses are investigated here with time-resolved flash photography, and they are found to occur whether or not the light-delivery fiber is in contact with the target. We demonstrate that the impulses depend primarily on the energy stored in the cavitation bubble. They are not directly dependent on the mode of light delivery (contact versus noncontact), and they are also not directly correlated to the other acoustic transients. The pressure impulses do …


Flow And Congestion Control For Internet Streaming Applications, Shanwei Cen, Calton Pu, Jonathan Walpole Dec 1997

Flow And Congestion Control For Internet Streaming Applications, Shanwei Cen, Calton Pu, Jonathan Walpole

Computer Science Faculty Publications and Presentations

The emergence of streaming multimedia players provides users with low latency audio and video content over the Internet. Providing high-quality, best-effort, real-time multimedia content requires adaptive delivery schemes that fairly share the available network bandwidth with reliable data protocols such as TCP. This paper proposes a new flow and congestion control scheme, SCP (Streaming Control Protocol) , for real-time streaming of continuous multimedia data across the Internet. The design of SCP arose from several years of experience in building and using adaptive real-time streaming video players. SCP addresses two issues associated with real-time streaming. First, it uses a congestion control …


Routing, Driven Placement For Atmel 6000 Architecture Fpgas, Songhua Zhang Nov 1997

Routing, Driven Placement For Atmel 6000 Architecture Fpgas, Songhua Zhang

Dissertations and Theses

Based on the concept of Cell Binary Tree (CBT), a new technique for mapping combination circuits into ATMEL 6000 Architecture FPGAs is presented in this thesis. Cell Binary Tree (CBT) is a net-list representation of combinational circuits. For each node of CBT there is a distinguished variable associated with it, the node itself represents a certain logic function, which is selected according to target FPGA architecture. The proposed CBT placement algorithms preserve local connectivity and allow better mapping into ATMEL FPGA. Experiments reveal that the new mapping technique achieved reduction in a number buses used for routing comparing with previously …


Waterfall Lasers, Lee W. Casperson Nov 1997

Waterfall Lasers, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

Laser concepts can be applied to a broad range of physical phenomena. One of the closest parallels occurs with the fluttering oscillations that are sometimes observed in the falling sheets of water associated with fountains, dams, and natural waterfalls. In many respects these fluid feedback oscillations are similar to the electromagnetic modes of typical lasers, and recognition of this similarity led to the interpretation of the waterfall behavior. Gain profiles for the waterfall oscillations are developed, and the relationship of experimental waterfall data to the laser-like models is considered in detail.


A Player For Adaptive Mpeg Video Streaming Over The Internet, Jonathan Walpole, Rainer Koster, Shanwei Cen, Crispin Cowan, David Maier, Dylan Mcnamee, Calton Pu, David Steere, Liujin Yu Oct 1997

A Player For Adaptive Mpeg Video Streaming Over The Internet, Jonathan Walpole, Rainer Koster, Shanwei Cen, Crispin Cowan, David Maier, Dylan Mcnamee, Calton Pu, David Steere, Liujin Yu

Computer Science Faculty Publications and Presentations

This paper describes the design and implementation of a real-time, streaming, Internet video and audio player. The player has a number of advanced features including dynamic adaptation to changes in available bandwidth, latency and latency variation; a multi-dimensional media scaling capability driven by user-specified quality of service (QoS) requirements; and support for complex content comprising multiple synchronized video and audio streams. The player was developed as part of the QUASAR t project at Oregon Graduate Institute, is freely available, and serves as a testbed for research in adaptive resource management and QoS control.


Modeling Improvements For Water Supply Forecasting In The Columbia River Basin, Daniel Albert Buller Aug 1997

Modeling Improvements For Water Supply Forecasting In The Columbia River Basin, Daniel Albert Buller

Dissertations and Theses

The purposes of this study were twofold. The first was to explore possible improvements that could be made over existing methods by applying alternative modeling approaches, including the one developed by Garen to forecast runoff volumes in the Columbia River at The Dalles, Oregon. The second was to use the Southern Oscillation as one of the variables to forecast spring and summer runoff and to evaluate whether this variable adds significant information early in the season before any snow has accumulated. The Columbia River basin's mountainous topography and northern latitude are ideally suited for water supply forecasting because much of …


High-Performance Input/Output Circuit For Cmos Integrated Circuit Interface, Chee How Lim Jul 1997

High-Performance Input/Output Circuit For Cmos Integrated Circuit Interface, Chee How Lim

Dissertations and Theses

In recent years, strong demand for high-performance electronic products has fueled the need for high-speed and high-integration VLSI circuits. This demand is expected to continue growing in the future, which will lead to development of IC's that are much more compact and operate at higher frequencies. As a result. preserving signal integrity for proper IC communications becomes an increasingly difficult challenge. In this thesis, an understanding of IC noise in relation to IC packaging is sought. An IC package is modeled with sophisticated 3-D simulators to extract its corresponding parasitics. These parasitics. expressed in terms of resistance. inductance. and capacitance …


Dynamic Load Distribution In Mist, K. Al-Saqabi, R. M. Prouty, Dylan Mcnamee, Steve Otto, Jonathan Walpole Jul 1997

Dynamic Load Distribution In Mist, K. Al-Saqabi, R. M. Prouty, Dylan Mcnamee, Steve Otto, Jonathan Walpole

Computer Science Faculty Publications and Presentations

This paper presents an algorithm for scheduling parallel applications in large-scale, multiuser, heterogeneous distributed systems. The approach is primarily targeted at systems that harvest idle cycles in general-purpose workstation networks, but is also applicable to clustered computer systems and massively parallel processors. The algorithm handles unequal processor capacities, multiple architecture types and dynamic variations in the number of processes and available processors. Scheduling decisions are driven by the desire to minimize turnaround time while maintaining fairness among competing applications. For efficiency, the virtual processors (VPs) of each application are gang scheduled on some subset of the available physical processors.


Limitations Of Methods For Determining The Position Of The Center Of Mass Of A Human Subject Performing A Sit-Up, Terrence Chadwick Smith Jun 1997

Limitations Of Methods For Determining The Position Of The Center Of Mass Of A Human Subject Performing A Sit-Up, Terrence Chadwick Smith

Dissertations and Theses

The knowledge of the position of the center of mass of a human subject performing a sit-up could help us understand the coordination of the sit-up motion. This thesis investigates the limits in three methods of determining the center of mass of a human subject. The three methods are the anthropometric method, the dynamic method, and the static torque method. The anthropometric method is a standard method that uses measurements of the subject to estimate the mass properties of individual segments of the body. The center of mass of the body is calculated from the mass and positions of the …


The Column Multiplicity Problem In Decomposition Of Functions And Relations, Rahul Malvi Jun 1997

The Column Multiplicity Problem In Decomposition Of Functions And Relations, Rahul Malvi

Dissertations and Theses

Finding the column multiplicity in Functional Decomposition has been known to be one of the most important problems to be solved in the process of functional decomposition of discrete functions. A lot of research has been done in this field with many new heuristics generated to find the column multiplicity, but there has not been an evaluation of the algorithms on the kinds of graphs that occur in decomposition and whether having an exact method to calculate the column multiplicity is useful from the overall design goals.The intent of this thesis was to investigate the column multiplicity problem, in order …


A Toolkit For Specializing Production Operating System Code, Crispin Cowan, Dylan Mcnamee, Andrew P. Black, Calton Pu, Jonathan Walpole, Charles Krasic, Perry Wagle, Qian Zhang Jun 1997

A Toolkit For Specializing Production Operating System Code, Crispin Cowan, Dylan Mcnamee, Andrew P. Black, Calton Pu, Jonathan Walpole, Charles Krasic, Perry Wagle, Qian Zhang

Computer Science Faculty Publications and Presentations

Specialization has been recognized as a powerful technique for optimizing operating systems. However, specialization has not been broadly applied beyond the research community because the current techniques, based on manual specialization, are time-consuming and error-prone. This paper describes a specialization toolkit that should help broaden the applicability of specializing operating systems by assisting in the automatic generation of specialized code, and {\em guarding} the specialized code to ensure the specialized system continues to be correct. We demonstrate the effectiveness of the toolkit by describing experiences we have had applying it in real, production environments. We report on our experiences with …


Training Strategies For Critic And Action Neural Networks In Dual Heuristic Programming Method, Christian Peter Paintz May 1997

Training Strategies For Critic And Action Neural Networks In Dual Heuristic Programming Method, Christian Peter Paintz

Dissertations and Theses

This thesis discusses strategies for and details of training procedures for the Dual Heuristic Programming (DHP) methodology. This and other approximate dynamic programming approaches (HDP, DHP, GDHP) have been discussed in some detail in the literature, all being members of the Adaptive Critic Design (ACD) family. The example applications used here are the inverted pendulum problem and a fully nonlinear constant velocity bicycle steering model. The inverted pendulum has been successfully controlled using DHP, as reported in the literature. This thesis suggests and investigates several alternative D HP training procedures and compares their performance with respect to convergence speed and …


Predictable File Access Latency For Multimedia, Dan Revel, Crispin Cowan, Dylan Mcnamee, Calton Pu, Jonathan Walpole May 1997

Predictable File Access Latency For Multimedia, Dan Revel, Crispin Cowan, Dylan Mcnamee, Calton Pu, Jonathan Walpole

Computer Science Faculty Publications and Presentations

Multimedia applications are sensitive to I/O latency and jitter when accessing data in secondary storage. Transparent adaptive prefetching (TAP) uses software feedback to provide multimedia applications with file system quality of service (QoS) guarantees. We are investigating how QoS requirements can be communicated and how they can be met by adaptive resource management. A preliminary test of adaptive prefetching is presented.


Generalized Beam Matrices. Iv. Optical System Design, Anthony A. Tovar, Lee W. Casperson Apr 1997

Generalized Beam Matrices. Iv. Optical System Design, Anthony A. Tovar, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

Systematic procedures are presented for determining the optical components needed to produce an arbitrary transformation of a Gaussian light beams's spot size, radius of curvature, displacement, and direction of propagation. As an example, an optical system is considered that spatially separates the two coincident Gaussian beams produced by a high-diffraction-loss resonator that uses a Gaussian variable-reflectivity output coupler. In addition, an ABCDGH reverse matrix theorem and an ABCDGH Sylvester theorem are also derived. These matrix theorems may be used to satisfy special constraints inherent in the design of multipass and periodic optical systems.


Rate-Equation Approximations In High-Gain Lasers, Lee W. Casperson Apr 1997

Rate-Equation Approximations In High-Gain Lasers, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

The rate-equation approximation is one of the most fundamental and universally employed simplifications in laser analyses. The accuracy and regions of applicability of this approximation are explored in comparisons with more rigorous semiclassical models. Higher-order rate-equation approximations are also developed, and these improved models can yield much better accuracy than conventional rate equations with little added complexity. The modified adiabatic elimination methods reported here would also be useful in reducing the mathematical models governing other physical systems.


Automatic Synthesis Of Vlsi Layout For Cmos Continuous-Time Filters, Wei Han Mar 1997

Automatic Synthesis Of Vlsi Layout For Cmos Continuous-Time Filters, Wei Han

Dissertations and Theses

Automatic synthesis of digital VLSI layout has been available for many years. It has become a necessary part of the design industry as the window of time from conception to production shrinks with ever increasing competition. However, automatic synthesis of analog VLSI layout remains rare.

With digital circuits, there is often room for signal drift. In a digital circuit, a signal can drift within a range before hitting the threshold which triggers a change in logic state. The effect of parasitic capacitances for the most part, hinders the timing margins of the signal, but not its functionality. The logic functionality …


Interaction Of Fluctuating River Flow With A Barotropic Tide: A Demonstration Of Wavelet Tidal Analysis Methods, David A. Jay, Edward P. Flinchem Mar 1997

Interaction Of Fluctuating River Flow With A Barotropic Tide: A Demonstration Of Wavelet Tidal Analysis Methods, David A. Jay, Edward P. Flinchem

Civil and Environmental Engineering Faculty Publications and Presentations

Wavelet transforms provide a valuable new tool for analysis of tidal processes that deviate markedly from an assumption of exact periodicity inherent in traditional harmonic analysis. A wavelet basis adapted to nonstationary tidal problems is constructed and employed to analyze the modulation of the external tide in a river by variations in streamflow. Interaction of a surface tide with river flow is the best available demonstration of the continuous wavelet transform (CWT) methods developed. It is the simplest and perhaps the only nonstationary tidal process for which both sufficient data and dynamical understanding exist to allow detailed comparisons between CWT …


Tool Condition Monitoring: A Computational Approach, Anthony Clinch Mar 1997

Tool Condition Monitoring: A Computational Approach, Anthony Clinch

Dissertations and Theses

Tool Condition Monitoring offers a new approach to reducing the costs associated with catastrophic tool failure. The manufacturing process is becoming more computationally oriented all the time. Computational methods of determining the condition of cutting tools will lend themselves to easy integration with current and forthcoming manufacturing techniques. Coupling the results of this computational approach with a cost analysis will provide a means of maximizing the investment in cutting tools, while minimizing the damage caused by tool failure. Tool Condition Monitoring, as defined here, is a method of computationally determining the condition of a cutting tool. The problem of determining …


Dominant Wave Directions And Significant Wave Heights From Synthetic Aperture Radar Imagery Of The Ocean, Lisa M. Zurk, William J. Plant Feb 1997

Dominant Wave Directions And Significant Wave Heights From Synthetic Aperture Radar Imagery Of The Ocean, Lisa M. Zurk, William J. Plant

Electrical and Computer Engineering Faculty Publications and Presentations

We show that quasi-linear theory accounts for dominant wave directions observed in synthetic aperture radar (SAR) imagery of the ocean for range-to-velocity (R/V) ratios up to 70 s. We also show that when used in combination with Alpers and Hasselmann's [1982] model of signal-to-noise ratios in SAR imagery, this theory yields significant wave heights in good agreement with those actually observed. We have found that the apparent dominant wave direction in SAR imagery taken at a 45° incidence angle can differ from the true wave direction by as much as 40° under certain conditions. To understand such differences, we simulated …


A Simplified Approach To Reduce Blocking And Ringing Artifacts In Transform-Coded Images, Jianping Hu Feb 1997

A Simplified Approach To Reduce Blocking And Ringing Artifacts In Transform-Coded Images, Jianping Hu

Dissertations and Theses

Presently Block-based Discrete Cosine Transform (BDCT) image coding techniques are widely used in image and video compression applications such as JPEG and MPEG. At a moderate bit rate, BDCT is usually a quite satisfactory solution to most of practical coding applications. However, for high rate compression it produces noticeable blocking and ringing artifacts in the decompressed image. It has been an active research area for a decade for reducing these artifacts. In this thesis, a novel post-processing algorithm is proposed to remove the blocking and ringing artifacts at low bit rate. It is non-iterative and uses both spatial and transform …


Data Envelopment Analysis With Integral Targets, Gunter P. Sharp, Timothy R. Anderson Jan 1997

Data Envelopment Analysis With Integral Targets, Gunter P. Sharp, Timothy R. Anderson

Engineering and Technology Management Faculty Publications and Presentations

Data Envelopment Analysis (DEA) inherently assumes that the feasible targets for inputs and outputs are continuous. This paper develops and illustrates extensions to DEA that allow for integer valued inputs and outputs. It is found that DEA?s implicit assumption of continuous targets can be significant in certain applications.


Incentives, Information, And Winner's Curse In Construction Industry Bidding, Gerald H. Williams, Timothy R. Anderson Jan 1997

Incentives, Information, And Winner's Curse In Construction Industry Bidding, Gerald H. Williams, Timothy R. Anderson

Engineering and Technology Management Faculty Publications and Presentations

This paper investigates the relationship between incentives, information and winner's curse in the bidding for construction industry contracts. The approach uses both simple Monte Carlo simulations and bidding experiments to show the effects of changing levels of information (in terms of variance) and incentive (in terms of risk share) on the winner's curse.


An Introduction To Data Envelopment Analysis In Technology Management, Keith Hollingsworth, Timothy R. Anderson Jan 1997

An Introduction To Data Envelopment Analysis In Technology Management, Keith Hollingsworth, Timothy R. Anderson

Engineering and Technology Management Faculty Publications and Presentations

Productivity is a major source of competitive advantage but improving productivity requires analysis and productivity is getting more difficult to measure as economies become more knowledge, service, and innovation intensive. In this paper, we will provide an introduction to a powerful productivity analysis tool, Data Envelopment Analysis (DEA). DEA is a flexible tool originally created in the 1970s for examining the relative efficiency of non-profit institutions. Researchers have found many more applications and created numerous extensions to DEA. This paper provides an introduction to DEA, a summary of some of the most important modeling variations, and examples of applications relevant …


A New Measure Of Baseball Batters Using Dea, Timothy R. Anderson, Gunter P. Sharp Jan 1997

A New Measure Of Baseball Batters Using Dea, Timothy R. Anderson, Gunter P. Sharp

Engineering and Technology Management Faculty Publications and Presentations

Data Envelopment Analysis (DEA) is used to create an alternative to traditional batting statistics called the Composite Batter Index (CBI). Advantages of CBI over traditional statistics include the fact that players are judged on the basis of what they accomplish relative to other players and that it automatically accounts for changing conditions of the game that raise or lower batting statistics. Historical results are examined to show how the industry of baseball batting has matured and potential uses of CBI are discussed. The application of baseball suggests that random variation may have an effect on CBI. We investigated this effect …


Selecting The "Best" Using Data Envelopment Analysis, Timothy R. Anderson, Akin Uslu Jan 1997

Selecting The "Best" Using Data Envelopment Analysis, Timothy R. Anderson, Akin Uslu

Engineering and Technology Management Faculty Publications and Presentations

One of the most important strengths of Data Envelopment Analysis, (DEA), is that it allows almost complete freedom in the way that each decision making unit, (DMU), evaluates itself relative to its peers. This tends to result in many DMUs receiving a high efficiency score. Particularly when DEA is applied in a decision making context, it may be desirable to select a single option rather than determining the set of efficient alternatives in ranking efficient DMU or to Assist selecting a "best" DMU. Several extensions to DEA have been proposed and used. This paper examines, compares, and integrates a variety …


Complete-Range Activity-Based Rtl Power Estimation, Nur Kurt-Karsilayan Jan 1997

Complete-Range Activity-Based Rtl Power Estimation, Nur Kurt-Karsilayan

Dissertations and Theses

In recent years, power consumption has become a major concern in the electronic industry. Power reduction can be accelerated in the design cycle by fast and accurate power estimation tools. Since the units of lower-levels of design abstraction are transistors or gates, power estimation becomes a slow process at these levels. Therefore designers need to have tools for fast and accurate power estimation at the higher levels of design abstraction such as register transfer level (RTL).

A novel RTL power estimation technique called CRAB-RPE will be presented in this thesis. The CRAB power model is built upon four important properties …


Achieving Cochannel Interference Objectives Over Selected Topologies In The Portland, Oregon Cellular Network, David A. Wand Jan 1997

Achieving Cochannel Interference Objectives Over Selected Topologies In The Portland, Oregon Cellular Network, David A. Wand

Dissertations and Theses

Wireless cellular mobile communications is a rapidly growing global technology which places increasing demands on a limited electromagnetic radio frequency spectrum. However, in North America only a 25 MHz block of spectrum has been allocated to each of two service providers. This must be utilized for all services offered within their assigned market.

The wireless cellular link from the mobile or portable phone to terrestrial base stations utilize this limited frequency spectrum. This is divided into 416 two-way channels, each 30 kHz in width, a subset of which is assigned to each base station. As more base stations are constructed, …


Erp Analysis Using Matched Filtering, Correlation Coefficient And Mann-Whitney Test, Yun Yan Jan 1997

Erp Analysis Using Matched Filtering, Correlation Coefficient And Mann-Whitney Test, Yun Yan

Dissertations and Theses

Event related potentials (ERPs) carry very important information that relate to the performance of the brain functions of a human being. Further studies have identified that the late positive complex (LPC) are affected by the memory process.

The matched filter method is used to improve the signal -to-noise ratio of signal ERPs. We use the output of the matched filter to distinguish the difference of the waveforms. In our study, we found that the peak values of the matched filter output differed among normal subjects and memory-impaired subjects.

The correlation coefficient is a statistical value that can be applied to …