Physical Sciences and Mathematics Commons^™

Variable Rate Execution, Steve Goddard, Xin Liu

CSE Technical Reports

We present a task model for adaptive real-time tasks in which a task’s execution rate requirements are allowed to change at any time. The model, variable rate execution (VRE), is an extension of the rate-based execution (RBE) model. We relax the constant execution rate assumption of canonical realtime task models by allowing both the worst case execution time (WCET) and the period to be variable. The VRE model also supports tasks joining and leaving the system at any time. Another advantage of the new task model is that the exact execution rate need not be known for soft real-time or …

A Dynamic Real-Time Scheduling Algorithm For Reduced Energy Consumption, Rohini Krishnapura, Steve Goddard, Ala' Adel Qadi

CSE Technical Reports

In embedded real-time systems, Dynamic Power Management (DPM) techniques have traditionally focused on reducing the dynamic power dissipation that occurs when a CMOS gate switches in a processor. Less attention has been given to processor leakage power or power consumed by I/O devices and other subsystems. I/O-based DPM techniques, however, have been extensively researched in non-real-time systems. These techniques focus on switching I/O devices to low power states based on various policies and are not applicable to real-time environments because of the non-deterministic nature of the policies. The challenge in conserving energy in embedded real-time systems is thus to reduce …

Ilmda: Intelligent Learning Materials Delivery Agents, Leen-Kiat Soh, L.D. Miller, Todd Blank, Suzette Person

CSE Technical Reports

In this paper, we describe an intelligent agent that delivers learning materials adaptively to different students, factoring in the usage history of the learning materials, the student static background profile, and the student dynamic activity profile. Our assumption is that through the interaction of a student going through a learning material (i.e., a topical tutorial, a set of examples, and a set of problems), our agent will be able to capture and utilize the student’s activity as the primer to select the appropriate example or problem to administer to the student. Even if the agent fails to do so, it …

Survivable Virtual Topology Routing Under Shared Risk Link Groups In Wdm Networks, Ajay Todimala, Byrav Ramamurthy

CSE Conference and Workshop Papers

Network survivability is one of the most important issues in the design of optical WDM networks. In this work we study the problem of survivable routing of a virtual topology on a physical topology with Shared Risk Link Groups (SRLG). The survivable virtual topology routing problem against single-link failures in the physical topology is proved to be NP-complete in [1]. We prove that survivable virtual topology routing problem against SRLG/node failures is also NP-complete. We present an improved integer linear programming (ILP) formulation (in comparison to [1]) for computing the survivable routing under SRLG/node failures. Using an ILP solver, we …

On Cooperative Learning Teams For Multiagent Team Formation, Leen-Kiat Soh

CSE Technical Reports

In this paper, we propose a team formation methodology based on cooperative learning teams, adopted from the area of educational research. Cooperative learning is a type of learning where students work in teams and learn through team-based interactions. In education, research in assigning students to appropriate teams and enforcing fair assessment of student performance in a team have generated useful policies and rules. In our multiagent systems project, we use these policies and rules as the underlying framework to evaluate and form teams. We have built a system called I-MINDS as an infrastructure to support cooperative learning among remote and …

Reasoning And Learning With Imperfect Casebases: An Agent Perspective With An Expert Model, Leen-Kiat Soh

CSE Technical Reports

Traditionally, case-based reasoning (CBR) (e.g., Watson and Marir 1994) assumes that the cases in the casebase are correct, useful in both time and space. Otherwise, the cases would not have been stored in the casebase in the first place. Cases are supposed to be useful in guiding us to a successful solution, or in preventing us from repeating the same failure.

Optimization Of Conditions For Studies Of Protein Unfolding By Hydrogen Exchange/Mass Spectrometry, A.S. Raza, David L. Smith

Chemistry Department: Faculty Publications

Understanding the forces driving protein folding and aggregation is an essential step in developing means for controlling these important processes. Amide hydrogen exchange, coupled with mass spectrometry, has become an important method for studying protein unfolding and refolding. To extend procedures developed to study unfolding of relatively soluble proteins to less soluble, aggregation-prone proteins requires special considerations. This publication describes a general strategy developed using yeast transaldolase, which aggregates easily under conditions required to study its unfolding. Results presented here show that reducing the protein concentration to the nanomolar range is essential for managing aggregation of transaldolase. In addition, the …

Tem Study Of Crystalline Structures Of Cr–N Thin Films, Xingzhong Li, J. Zhang, David J. Sellmyer

Nebraska Center for Materials and Nanoscience: Faculty Publications

Cr–N films were grown on Si (001) substrates by reactive magnetron sputtering under an N2/Ar atmosphere at room temperature. The composition of the films, expressed as Cr_1–xN_x, can be varied by changing the N₂/Ar pressure ratio during the synthesis process. Crystalline states of Cr–N films have been studied using electron diffraction. It is well known that two intermediate phases, Cr₂N (hexagonal) and CrN (cubic), exist in the Cr–N system, and small variations around the ideal stoichiometry are tolerated. The present study shows that cubic CrN with vacancies rather than hexagonal Cr_{2 …}

Water Quality Assessment: A Hands-On Approach To Environmental Education, Tracy Lynn Royse

All Graduate Projects

A water quality assessment lab manual has been created to assist secondary educators using the HACH water quality testing kits. It consists of ten chemical tests, a geological survey and a biological assessment largely based upon Washington State University's lab format and the Walla Walla County Conservation District's water study protocol. The lab manual also contains safety guidelines, a scoring rubric and an action plan research project. The environmental approach to science education used in the lab manual meets the Essential Academic Learning Requirements adopted by the Washington State Commission on Student Learning as well as the National Science Education …

Tr-2004001: Tableaux For The Logic Of Proofs, Bryan Renne

Computer Science Technical Reports

No abstract provided.

Tr-2004002: Oopn: An Object-Oriented Petri Nets And Its Integrated Development Environment, Jinzhong Niu, Jing Zou, Aihua Ren

Computer Science Technical Reports

No abstract provided.

Tr-2004004: Implementing And Automating Basic Number Theory In Metaprl Proof Assistant, Yegor Bryukhov, Alexei Kopylov, Vladimir Krupski, Aleksey Nogin

Computer Science Technical Reports

No abstract provided.

Tr-2004010: Optimal Reversible Quantum Circuit For Multiplication, Anh Quoc Nguyen

Computer Science Technical Reports

No abstract provided.

Tr-2004009: A Reduction Of The Matrix Eigenproblem To Polynomial Rootfinding Via Similarity Transforms Into Arrow-Head Matrices, Victor Y. Pan

Computer Science Technical Reports

No abstract provided.

Tr-2004011: Logic Of Knowledge With Justifications From The Provability Perspective, Sergei Artemov, Elena Nogina

Computer Science Technical Reports

No abstract provided.

Tr-2004012: Single-Hop Probing Asymptotics In Available Bandwidth Estimation: Sample-Path Analysis, Xiliang Liu, Kaliappa Ravindran, Benyuan Liu, Dmitri Loguinov

Computer Science Technical Reports

No abstract provided.

Tr-2004007: Optimal Reversible Quantum Circuit For Multiplication, Anh Quoc Nguyen

Computer Science Technical Reports

No abstract provided.

Tr-2004016: Semantics And Tableaus For Lps4, Melvin Fitting

Computer Science Technical Reports

No abstract provided.

Tr-2004019: Quantified Lp, Melvin Fitting

Computer Science Technical Reports

No abstract provided.

Coastal Lakes Aquatic Plant Survey Report, Mary Pfauth, Mark Sytsma

Center for Lakes and Reservoirs Publications and Presentations

Invasive, non-indigenous plants can degrade water quality and fish habitat when they invade lakes, ponds, and streams. Changes in plant community architecture in lakes due to invasion by canopy-forming invasive aquatic plants can result in loss of native plant biodiversity and reduction of the structural complexity of the underwater habitat. Differences in photosynthetic biochemistry between non-indigenous and native plants can result in large diurnal pH and dissolved oxygen concentrations.

2004 Gloucester Point Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans

Miscellaneous

These calendars are produced monthly using David Evans' Tidecal.

Pupil Phase Apodization For Achromatic Imaging Of Extra-Solar Planets, Weidong Yang

Dissertations, Master's Theses and Master's Reports - Open

Direct imaging of extra-solar planets in the visible and infrared region has generated great interest among scientists and the general public as well. However, this is a challenging problem. Diffculties of detecting a planet (faint source) are caused, mostly, by two factors: sidelobes caused by starlight diffraction from the edge of the pupil and the randomly scattered starlight caused by the phase errors from the imperfections in the optical system. While the latter diffculty can be corrected by high density active deformable mirrors with advanced phase sensing and control technology, the optimized strategy for suppressing the diffraction sidelobes is still …

Application Of Well Log Tomography To The Dundee And Rogers City Limestones, Michigan Basin, Usa, Mellisa A. Le M.

Dissertations, Master's Theses and Master's Reports - Open

The Michigan Basin is located in the upper Midwest region of the United States and is centered geographically over the Lower Peninsula of Michigan. It is filled primarily with Paleozoic carbonates and clastics, overlying Precambrian basement rocks and covered by Pleistocene glacial drift. In Michigan, more than 46,000 wells have been drilled in the basin, many producing significant quantities of oil and gas since the 1920s in addition to providing a wealth of data for subsurface visualization.

Well log tomography, formerly log-curve amplitude slicing, is a visualization method recently developed at Michigan Technological University to correlate subsurface data by utilizing …

Hydrogeochemical Controls On Uranium In Aquifers Of The Jacobsville Sandstone, Heidi M. Sherman

Dissertations, Master's Theses and Master's Reports - Open

The occurrence of elevated uranium (U) in sandstone aquifers was investigated in the Upper Peninsula of Michigan, focusing on aquifers of the Jacobsville Sandstone. The hydrogeochemical controls on groundwater U concentrations were characterized using a combination of water sampling and spectral gamma-ray logging of sandstone cliffs and residential water wells. ²³⁵U/²³⁸U isotope ratios were consistent with naturally occurring U. Approximately 25% of the 270 wells tested had U concentrations above the U.S. Environmental Protection Agency Maximum Contaminant Level (MCL) of 30 μg/L, with elevated U generally occurring in localized clusters. Water wells were logged to determine whether …

Dating The Siple Dome (Antarctica) Ice Core By Manual And Computer Interpretation Of Annual Layering, Kendrick C. Taylor, Richard B. Alley, Debra A. Meese, Matthew K. Spencer, Ed J. Brook, Nelia W. Dunbar, Robert C. Finkel, Anthony J. Gow, Andrei V. Kurbatov, Gregg W. Lamorey, Paul Andrew Mayewski, Eric A. Meyerson, Kunihiko Nishiizumi, Gregory A. Zielinski

Earth Science Faculty Scholarship

The Holocene portion of the Siple Dome (Antarctica) ice core was dated by interpreting the electrical, visual and chemical properties of the core. The data were interpreted manually and with a computer algorithm. The algorithm interpretation was adjusted to be consistent with atmospheric methane stratigraphic ties to the GISP2 (Greenland Ice Sheet Project 2) ice core, (BE)-B-10 stratigraphic ties to the dendrochronology C-14 record and the dated volcanic stratigraphy. The algorithm interpretation is more consistent and better quantified than the tedious and subjective manual interpretation.

Ice Dynamics Preceding Catastrophic Disintegration Of The Floating Part Of Jakobshavn Isbrie, Greenland, Jesse V. Johnson, Paul R. Prescott, Terence J. Hughes

Earth Science Faculty Scholarship

The floating terminal of Jakobshavn Isbr ae, the fastest Greenland ice stream, has disintegrated since 2002, resulting in a doubling of ice velocity and rapidly lowering inland ice elevations. Conditions prior to disintegration were modeled using control theory in a plane-stress solution, and the Missoula model of ice-shelf flow. Both approaches pointed to a mechanism that inhibits ice flow and that is not captured by either approach. Jamming of flow, an inherent property of granular materials passing through a constriction (Jakobshavn Isfjord), is postulated as the mechanism. Rapid disintegration of heavily crevassed floating ice accompanies break-up of the ice jam.

A 200 Year Sub-Annual Record Of Sulfate In West Antarctica, From Sixteen Ice Cores, D. Dixon, Paul Andrew Mayewski, S. Kaspari, Sharon B. Sneed, M. Handley

Earth Science Faculty Scholarship

Sixteen high-resolution ice-core records from West Antarctica and South Pole are used to examine the spatial and temporal distribution of sulfate for the last 200 years. The preservation of seasonal layers throughout the length of each record results in a dating accuracy of better than 1 year based on known global-scale volcanic events. A dual transport source for West Antarctic sea-salt (ss) SO42- and excess (xs) SO42- is observed: lower-tropospheric for areas below 1000m elevation and mid-/upper-tropospheric/stratospheric for areas located above 1000m. Our XsSO(4)(2-) records with volcanic peaks removed do not display any evidence of an anthropogenic impact on West …

A 700 Year Record Of Southern Hemisphere Extratropical Climate Variability, Paul Andrew Mayewski, Kirk A. Maasch, J W.C. White, E. J. Steig, E. Meyerson, I. Goodwin, V. I. Morgan, T. Van Ommen, M. A.J. Curran, J. Souney, Karl Kreutz

Earth Science Faculty Scholarship

Annually dated ice cores from West and East Antarctica provide proxies for past changes in atmospheric circulation over Antarctica and portions of the Southern Ocean, temperature in coastal West and East Antarctica, and the frequency of South Polar penetration of El Nino events. During the period (AD) 1700-1850, atmospheric circulation over the Antarctic and at least portions of the Southern Hemisphere underwent a mode switch departing from the out-of-phase alternation of multi-decadal long phases of EOF1 and EOF2 modes of the 850 hPa field over the Southern Hemisphere (as defined in the recent record by Thompson and Wallace, 2000; Thompson …

Climate Variability In West Antarctica Derived From Annual Accumulation-Rate Records From Itase Firn/Ice Cores, Susan D. Kaspari, Paul Andrew Mayewski, Daniel A. Dixon, Vandy Blue Spikes, Sharon B. Sneed, Michael J. Handley, Gordon S. Hamilton

Earth Science Faculty Scholarship

Thirteen annually resolved accumulation-rate records covering the last similar to 200 years from the Pine Island-Thwaites and Ross drainage systems and the South Pole are used to examine climate variability over West Antarctica. Accumulation is controlled spatially by the topography of the ice sheet, and temporally by changes in moisture transport and cyclonic activity. A comparison of mean accumulation since 1970 at each site to the long-term mean indicates an increase in accumulation for sites located in the western sector of the Pine Island-Thwaites drainage system. Accumulation is negatively associated with the Southern Oscillation Index (Sol) for sites near the …

Monsoonal Circulation Of The Mcmurdo Dry Valleys, Ross Sea Region, Antarctica: Signal From The Snow Chemistry, Nancy A.N. Bertler, Paul Andrew Mayewski, Peter J. Barrett, Sharon B. Sneed, Michael J. Handley, Karl J. Kreutz

Earth Science Faculty Scholarship

McMurdo Dry Valleys (MDV, Ross Sea region, Antarctica) precipitation exhibits extreme seasonality in ion concentration, 3-5 orders of magnitude between summer and winter precipitation. To identify aerosol sources and investigate causes for the observed amplitude in concentration variability, four snow pits were sampled along a coast-Polar Plateau transect across the MDV. The elevation of the sites ranges from 50 to 2400 m and the distance from the coast from 8 to 93 km. Average chemistry gradients along the transect indicate that most species have either a predominant marine or terrestrial source in the MDV. Empirical orthogonal function analysis on the …