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Using Dynamic Optimization For Control Of Real Rate Cpu Resource Management Applications, Varin Vahia, Ashvin Goel, David Steere, Jonathan Walpole, Molly H. Shor Dec 2003

Using Dynamic Optimization For Control Of Real Rate Cpu Resource Management Applications, Varin Vahia, Ashvin Goel, David Steere, Jonathan Walpole, Molly H. Shor

Computer Science Faculty Publications and Presentations

In this paper we design a proportional-period optimal controller for allocating CPU to real rate multimedia applications on a general-purpose computer system. We model this computer system problem in to state space form. We design a controller based on dynamic optimization LQR tracking techniques to minimize short term and long term time deviation from the current time stamp and also CPU usage. Preliminary results on an experimental set up are encouraging.


Infrastructure For Performance Tuning Mpi Applications, Kathryn Marie Mohror Nov 2003

Infrastructure For Performance Tuning Mpi Applications, Kathryn Marie Mohror

Dissertations and Theses

Clusters of workstations are becoming increasingly popular as a low-budget alternative for supercomputing power. In these systems, message-passing is often used to allow the separate nodes to act as a single computing machine. Programmers of such systems face a daunting challenge in understanding the performance bottlenecks of their applications. This is largely due to the vast amount of performance data that is collected, and the time and expertise necessary to use traditional parallel performance tools to analyze that data.

The goal of this project is to increase the level of performance tool support for message-passing application programmers on clusters of …


Integrated Hydrologic And Hydrochemical Observations Of Hidden Creek Lake Jökulhlaups, Kennicott Glacier, Alaska, Suzanne P. Anderson, Joseph S. Walder, Robert S. Anderson, Erin R. Kraal, Michelle Cunico, Andrew G. Fountain, Dennis C. Trabant Oct 2003

Integrated Hydrologic And Hydrochemical Observations Of Hidden Creek Lake Jökulhlaups, Kennicott Glacier, Alaska, Suzanne P. Anderson, Joseph S. Walder, Robert S. Anderson, Erin R. Kraal, Michelle Cunico, Andrew G. Fountain, Dennis C. Trabant

Geology Faculty Publications and Presentations

Hidden Creek Lake (HCL), an ice-marginal lake impounded by Kennicott Glacier, Wrangell Mountains, Alaska, fills annually to ~20 to 30 x ~10⁶ m³ and then drains subglacially within 2 to 3 days. During the 1999 and 2000 jökulhlaups, we carried out a series of planned observations around the lake and in the Kennicott River, which drains the glacier. Approximately 20% of the lake volume was contained within a subglacial water ‘‘wedge’’ beneath the ice dam. The entire volume of the lake drains through the wedge; hydraulic head loss through this constriction may be responsible for the fairly symmetrical shape of …


Faculty Senate Monthly Packet October 2003, Portland State University Faculty Senate Oct 2003

Faculty Senate Monthly Packet October 2003, Portland State University Faculty Senate

Faculty Senate Monthly Packets

The October 2003 Monthly packet includes the October agenda and appendices and the Faculty Senate minutes and attachments from the meeting held June 2003.


Pressure-Induced Insulating State In An Organic Superconductor, Gary L. Gard, Javid Mohtasham, J. A. Schlueter, C. Pfleiderer, J. Wosnitza, J. Hagel Sep 2003

Pressure-Induced Insulating State In An Organic Superconductor, Gary L. Gard, Javid Mohtasham, J. A. Schlueter, C. Pfleiderer, J. Wosnitza, J. Hagel

Chemistry Faculty Publications and Presentations

The electronic-transport properties of the quasi-two-dimensional organic superconductor β″–(BEDT-TTF)₂SF₅CH₂CF₂SO₃, where BEDT-TTF stands for bisethylenedithio-tetrathiafulvalene, have been investigated in magnetic fields up to 15 T and under hydrostatic pressure up to about 14 kbars. Shubnikov–de Haas data reveal a nonmonotonic pressure dependence of the holelike Fermi surface, a roughly linear increase of the electron g factor, and an approximately linear decrease of the cyclotron effective mass. By assuming that the latter reflects the pressure-induced reduction of the superconducting coupling parameter λ the rapid reduction of the superconducting transition temperature Tc(p) can be reasonably well described by the modified McMillan equation. Above …


Adaptive Reflex Control For An Artificial Hand, Michele Flogheraiter, Giuseppina Gini, Marek Perkowski, Mikhail Pivtoraiko Sep 2003

Adaptive Reflex Control For An Artificial Hand, Michele Flogheraiter, Giuseppina Gini, Marek Perkowski, Mikhail Pivtoraiko

Electrical and Computer Engineering Faculty Publications and Presentations

In this paper we illustrate the properties and the morphology of a human like neural reflex controller, used to set the stiffness and joint positions of an anthropomorphic artificial hand. In particular we explain, by simulations results, its ability to emulate the myotatic human reflex, and its capacity to learn in real time the best control strategy. We also present the dynamic model of the joints and of the artificial muscles used in Blackfingers, our artificial hand.


A Browser For Incremental Programming, Andrew P. Black Sep 2003

A Browser For Incremental Programming, Andrew P. Black

Computer Science Faculty Publications and Presentations

Much of the elegance and power of Smalltalk comes from its programming environment and tools. First introduced more than 20 years ago, the Smalltalk browser enables programmers to “home in” on particular methods using a hierarchy of manually-defined classifications. By its nature, this classification scheme says a lot about the desired state of the code, but little about the actual state of the code as it is being developed. We have extended the Smalltalk browser with dynamically computed virtual categories that dramatically improve the browser’s support for incremental programming. We illustrate these improvements by example, and describe the algorithms used …


Modeling Carrier Behavior In Sequential Auction Transportation Markets, Miguel Andres Figliozzi, Hani S. Mahmassani, Patrick Jaillet Aug 2003

Modeling Carrier Behavior In Sequential Auction Transportation Markets, Miguel Andres Figliozzi, Hani S. Mahmassani, Patrick Jaillet

Civil and Environmental Engineering Faculty Publications and Presentations

Online markets for transportation services, in the form of Internet sites that dynamically match shipments (shippers? demand) and transportation capacity (carriers? offer) through auction mechanisms are changing the traditional structure of transportation markets. A general framework for the study of carriers? behavior in a sequential auction transportation marketplace is provided. The unique characteristics of these marketplaces and the sources of difficulty in analyzing the behavior of these marketplaces are discussed. Learning and behavior in a sequential Vickrey auction marketplace is analyzed and simulated. Some results and the overall behavioral framework are also discussed.


Changing Structure Of The Arms Trade: A Social Network Analysis, David Todd Kinsella Aug 2003

Changing Structure Of The Arms Trade: A Social Network Analysis, David Todd Kinsella

Political Science Faculty Publications and Presentations

The global arms trade should be understood not as a market but as a network, one that shares some important properties with networked forms of organization studied by sociologists. I make this argument and then employ quantitative methods developed for social network analysis in an effort to describe the evolving structure of the arms trade network since the end of World War II. That structure has changed significantly over the past fifty years. It became less dense in the early years of the cold war as newly independent states joined the society of states, but had yet to develop many …


Spontaneous Coherent Pulsations In 3.39-M He–Ne Standing-Wave Laser Oscillators, Pitak Chenkosol, Lee W. Casperson Aug 2003

Spontaneous Coherent Pulsations In 3.39-M He–Ne Standing-Wave Laser Oscillators, Pitak Chenkosol, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

Spontaneous pulsations similar to the type discovered in 3.51-μm Xe laser oscillators were reported several years ago in 3.39-μm He–Ne lasers, but no numerical interpretation of the He–Ne data has been given. The model for the Xe laser instability is adapted here to the He–Ne system, and the results include direct comparisons between theoretical calculations and published experimental data. Good agreement is obtained for the instability threshold, the pulsation frequencies, and many other features; and unmeasured but potentially useful pulsation characteristics are also readily obtained from the model.


Adaptive Live Video Streaming By Priority Drop, Jie Huang, Charles Krasic, Jonathan Walpole Jul 2003

Adaptive Live Video Streaming By Priority Drop, Jie Huang, Charles Krasic, Jonathan Walpole

Computer Science Faculty Publications and Presentations

In this paper we explore the use of Priority-progress streaming (PPS) for video surveillance applications. PPS is an adaptive streaming technique for the delivery of continuous media over variable bit-rate channels. It is based on the simple idea of reordering media components within a time window into priority order before transmission. The main concern when using PPS for live video streaming is the time delay introduced by reordering. In this paper we describe how PPS can be extended to support live streaming and show that the delay inherent in the approach can be tuned to satisfy a wide range of …


Assigning Projects To Project Managers In A Multiple-Project Management Environment: A Pilot Study Of A Decision Support Model, Peerasit Patanakul, Dragan Milošević, Timothy R. Anderson Jul 2003

Assigning Projects To Project Managers In A Multiple-Project Management Environment: A Pilot Study Of A Decision Support Model, Peerasit Patanakul, Dragan Milošević, Timothy R. Anderson

Engineering and Technology Management Faculty Publications and Presentations

Project assignment is considered one of the most critical project decisions since it influences the performance of projects, and eventually the performance of the organization. Despite its importance, the literature reveals two major gaps on project assignment criteria and methodology. To close these gaps, this study proposes an additional set of project assignment criteria and a systematic methodology for project assignments (DSM). By using the concepts of these case study research combined with a literature review, the important potential criteria for project assignments are identified. These criteria are used in conjunction with the concepts of the analytic hierarchy process (AHP) …


Simulation As A Tool For Evaluating Strategic Policies For Flexible Supply Chain Systems, Janice L. Forrester, Wayne W. Wakeland Jul 2003

Simulation As A Tool For Evaluating Strategic Policies For Flexible Supply Chain Systems, Janice L. Forrester, Wayne W. Wakeland

Complex Systems Faculty Publications and Presentations

The emergence of flexible supply chain systems (FSC) has sparked increased interest in real-time planning, scheduling, and logistics--with particular consideration for strategic implications and overall cost control. Important aspects of an FSC include forecasting, production, materials handling, transportation, and distribution center inventory. There exists a variety of software applications for addressing tactical issues, such as adaptive scheduling, and short term forecasting. However, these programs typically do not permit the user to assess the strategic implications of different policies for flexing capacity and making alternative commitments to manufacturing plants. Recently there has been increased interest in the use of simulation models …


A System Dynamics Model Of The Pacific Coast Rockfish Fishery, Wayne Wakeland, Olgay Cangur, Guillermo Rueda, Astrid Scholz Jul 2003

A System Dynamics Model Of The Pacific Coast Rockfish Fishery, Wayne Wakeland, Olgay Cangur, Guillermo Rueda, Astrid Scholz

Complex Systems Faculty Publications and Presentations

This paper presents a model of the dynamic behavior of the yellowtail rockfish of the Pacific Coast of the United States. The purpose of the model is to generate endogenously the historical data for fish population, fishing vessels, regulatory parameters, and fish harvest. The model was subjected to a variety of tests to determine its sensitivity to changes in key parameters and initial values, including extreme conditions. Model results indicate that acceptable biological catch and fleet capacity must be adjusted quickly in response to changing conditions, in order to improve fishery sustainability. Additional analysis reinforces the policy of setting the …


Using Reconstructability Analysis To Select Input Variables For Artificial Neural Networks, Stephen Shervais, Martin Zwick Jul 2003

Using Reconstructability Analysis To Select Input Variables For Artificial Neural Networks, Stephen Shervais, Martin Zwick

Complex Systems Faculty Publications and Presentations

We demonstrate the use of Reconstructability Analysis to reduce the number of input variables for a neural network. Using the heart disease dataset we reduce the number of independent variables from 13 to two, while providing results that are statistically indistinguishable from those of NNs using the full variable set. We also demonstrate that rule lookup tables obtained directly from the data for the RA models are almost as effective as NNs trained on model variables.


Evolved Reversible Cascades Realized On The Cam-Brain Machine (Cbm), Andrzej Buller, Marek Perkowski Jul 2003

Evolved Reversible Cascades Realized On The Cam-Brain Machine (Cbm), Andrzej Buller, Marek Perkowski

Electrical and Computer Engineering Faculty Publications and Presentations

This paper presents a new approach to reversible cascade evolution based on a 3D cellular automaton. As a research platform we used the ATR's CAMBrain Machine (CBM). Reversible circuits are investigated because they are expected to dissipate much less energy than their irreversible counterparts. One day they will be implemented as nano-scale 3-dimensional chips. A circuit is reversible if the number of its inputs equals the number of its outputs and there is a one-to-one mapping between spaces of input vectors and output vectors. This paper provides: (1) a brief introduction to reversible logic concentrating on definitions and properties of …


Faculty Senate Monthly Packet June 2003, Portland State University Faculty Senate Jun 2003

Faculty Senate Monthly Packet June 2003, Portland State University Faculty Senate

Faculty Senate Monthly Packets

The June 2003 Monthly packet includes the June agenda and appendices and the Faculty Senate minutes and attachments from the meeting held May 2003.


Vertical Nanowire Transistor In Flexible Polymer Foil, Jie Chen, Rolf Könenkamp Jun 2003

Vertical Nanowire Transistor In Flexible Polymer Foil, Jie Chen, Rolf Könenkamp

Physics Faculty Publications and Presentations

Fabrication and operation of a vertical nanowire field-effect transistor is reported. The device is prepared by growing vertical wires in the cylindrical pores of a polymer foil stack. The nanowirediameter is approximately 100 nm, the packing density up to 10⁸ cm⁻². The polymer foil stack consists of two polymer layers and an intermediate metal layer. Cylindrical holes are prepared in this stack by using fast ion irradiation and subsequent etching. Well-defined cylindrical openings with diameters between 50 and 150 nm are obtained. The semiconductor growth involves electrodeposition of the p-type quaternary compound CuSCN. Electrical measurements on first devices show transistor …


A Bounded Rationality Analysis Of The Cyprus Problem, Birol Yesilada, Jacek Kugler, Harry Anastasiou, Ahmet Sozen, Brian Efird Jun 2003

A Bounded Rationality Analysis Of The Cyprus Problem, Birol Yesilada, Jacek Kugler, Harry Anastasiou, Ahmet Sozen, Brian Efird

Political Science Faculty Publications and Presentations

The time frame for a final decision on the Cyprus problem is narrowing very rapidly. The latest peace plan proposed by the U.N. Secretary General Kofi Annan, known as the Annan Plan, to solve the problem between the Greek Cypriot (G/Cs) and Turkish Cypriot (T/Cs) communities underwent the last refinements in February 2003 to bridge the gap between the two sides. Yet, despite intense domestic (especially in the Turkish north) and international pressures on the two sides to sign the agreement the Turkish Cypriot leadership rejected the proposal as being insufficient in meeting their demands. Despite the apparent low in …


Morphological Biosignatures And The Search For Life On Mars, Sherry L. Cady, Jack D. Farmer, John P. Grotzinger, J. William Schopf, Andrew Steele Jun 2003

Morphological Biosignatures And The Search For Life On Mars, Sherry L. Cady, Jack D. Farmer, John P. Grotzinger, J. William Schopf, Andrew Steele

Geology Faculty Publications and Presentations

This report provides a rationale for the advances in instrumentation and understanding needed to assess claims of ancient and extraterrestrial life made on the basis of morphological biosignatures. Morphological biosignatures consist of bona fide microbial fossils as well as microbially influenced sedimentary structures. To be recognized as evidence of life, microbial fossils must contain chemical and structural attributes uniquely indicative of microbial cells or cellular or extracellular processes. When combined with various research strategies, high-resolution instruments can reveal such attributes and elucidate how morphological fossils form and become altered, thereby improving the ability to recognize them in the geological record …


Linearized Stability Analysis Of Accelerated Planar And Spherical Fluid Interfaces With Slow Compression, John D. Ramshaw, Peter A. Amendt May 2003

Linearized Stability Analysis Of Accelerated Planar And Spherical Fluid Interfaces With Slow Compression, John D. Ramshaw, Peter A. Amendt

Physics Faculty Publications and Presentations

We present linearized stability analyses of the effect of slow anisotropic compression or expansion on the growth of perturbations at accelerated fluid interfaces in both planar and spherical geometries. The interface separates two fluids with different densities, compressibilities, and compression rates. We show that a perturbation of large mode number on a spherical interface grows at precisely the same rate as a similar perturbation on a planar interface subjected to the same normal and transverse compression rates.


Evolutionary Algorithms For Beginners, Marek Perkowski May 2003

Evolutionary Algorithms For Beginners, Marek Perkowski

Electrical and Computer Engineering Faculty Publications and Presentations

This presentation offers a detailed introduction into the concepts and applications of evolutionary ideas in computing, adapted from genetics and evolution.


Faculty Senate Monthly Packet May 2003, Portland State University Faculty Senate May 2003

Faculty Senate Monthly Packet May 2003, Portland State University Faculty Senate

Faculty Senate Monthly Packets

The May 2003 Monthly packet includes the May agenda and appendices and the Faculty Senate minutes and attachments from the meeting held April 2004.


Psf Measurements On Back-Illuminated Ccds, Ralf Widenhorn, Alexander Weber, Morley M. Blouke, Albert J. Bae, Erik Bodegom May 2003

Psf Measurements On Back-Illuminated Ccds, Ralf Widenhorn, Alexander Weber, Morley M. Blouke, Albert J. Bae, Erik Bodegom

Physics Faculty Publications and Presentations

The spatial resolution of an optical device is generally characterized by either the Point Spread Function (PSF) or the Modulation Transfer Function (MTF). To directly obtain the PSF one needs to measure the response of an optical system to a point light source. We present data that show the response of a back-illuminated CCD to light emitted from a sub-micron diameter glass fiber tip. The potential well in back-illuminated CCD"s does not reach all the way to the back surface. Hence, light that is absorbed in the field-free region generates electrons that can diffuse into other pixels. We analyzed the …


Artifacts And Cultures-Of-Use In Intercultural Communication, Steven L. Thorne May 2003

Artifacts And Cultures-Of-Use In Intercultural Communication, Steven L. Thorne

World Languages and Literatures Faculty Publications and Presentations

This article develops a conceptual framework for understanding how intercultural communication, mediated by cultural artifacts (i.e., Internet communication tools), creates compelling, problematic, and surprising conditions for additional language learning. Three case studies of computer-mediated intercultural engagement draw together correlations between discursive orientation, communicative modality, communicative activity, and emergent interpersonal dynamics. These factors contribute to varying qualities and quantities of participation in the intercultural partnerships. Case one, "Clashing Frames of Expectation -- Differing Cultures-of-Use," suggests that the cultures-of-use of Internet communication tools, their perceived existence and on-going construction as distinctive cultural artifacts, differs interculturally just as communicative genre, pragmatics, and institutional …


Cellular Automata Realization Of Regular Logic, Andrzej Buller, Marek Perkowski May 2003

Cellular Automata Realization Of Regular Logic, Andrzej Buller, Marek Perkowski

Electrical and Computer Engineering Faculty Publications and Presentations

This paper presents a cellular-automatic model of a reversible regular structure called Davio lattice. Regular circuits are investigated because of the requirement of future (nano-) technologies where long wires should be avoided. Reversibility is a valuable feature because it means much lower energy dissipation. A circuit is reversible if the number of its inputs equals the number of its outputs and there is a one-to-one mapping between spaces of input vectors and output vectors. It is believed that one day regular reversible structures will be implemented as nanoscale 3-dimensional chips. This paper introduces the notion of the Toffoli gate and …


Glaciers Of The Mcmurdo Dry Valleys: Terrestrial Analog For Martian Polar Sublimation, Andrew G. Fountain, J. S. Kargel, Karen J. Lewis, D. R. Macayeal Apr 2003

Glaciers Of The Mcmurdo Dry Valleys: Terrestrial Analog For Martian Polar Sublimation, Andrew G. Fountain, J. S. Kargel, Karen J. Lewis, D. R. Macayeal

Geography Faculty Publications and Presentations

The surfaces of the Martian north and south polar residual caps are marked by unusual ice features: dark spiralesque troughs up to 1 km deep, 10 km wide and 300 km long appear on both ice caps, and circular pits that make up the “Swiss-cheese” terrain appear on the south polar cap. Both types of features are of interest to researchers as a potential means of understanding ice composition and flow rates. Some glaciers of the McMurdo Dry Valleys have surface features unknown elsewhere on terrestrial glaciers, including canyons over 6 km long, 100 m wide, and tens of meters …


A Computer Model Of Intracranial Pressure Dynamics During Traumatic Brain Injury That Explicitly Models Fluid Flows And Volumes, Wayne W. Wakeland, Brahm Goldstein, Louis Macovsky, James Mcnames Apr 2003

A Computer Model Of Intracranial Pressure Dynamics During Traumatic Brain Injury That Explicitly Models Fluid Flows And Volumes, Wayne W. Wakeland, Brahm Goldstein, Louis Macovsky, James Mcnames

Complex Systems Faculty Publications and Presentations

This report documents a computer model of intracranial pressure (ICP) dynamics that is used to evaluate clinical treatment options for elevated ICP during traumatic brain injury (TBI). The model uses fluid volumes as primary state variables and explicitly models fluid flows as well as the resistance, compliance, and pressure associated with each of the compartments (arteries and arterioles, capillary bed, veins, venous sinus, ventricles, and brain parenchyma). The model has been tested to assure that it reproduces a correct physiologic response to intra-and extra-parenchymal hemorrhage and edema, and to therapies directed at reducing ICP such as cerebral spinal fluid drainage, …


Faculty Senate Monthly Packet April 2003, Portland State University Faculty Senate Apr 2003

Faculty Senate Monthly Packet April 2003, Portland State University Faculty Senate

Faculty Senate Monthly Packets

The April 2003 Monthly packet includes the April agenda and appendices and the Faculty Senate minutes and attachments from the meeting held March 2003.


Watershed Data Organization And Project Prioritization, Joshua Darling Apr 2003

Watershed Data Organization And Project Prioritization, Joshua Darling

Environmental Science and Management Professional Master's Project Reports

The Oregon Coastal Salmon Restoration Initiative (OCSRI) (1197) is the first of several documents that have come to be known as the Oregon Plan for Salmon and watersheds (OPSW). The OCSRI indicates that protection and restoration of salmonid stocks and improvement in water quality are the main roles for state agencies within the Oregon Plan (EO09-01: 1(b)). The Oregon Plan specifies particular actions that state agencies must take to aid in salmon recovery and also directs the Governors Watershed Enhancement Board (GWEB) to help create and organize watershed councils responsible for assessing conditions and determining priorities for watershed health. A …