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Western Washington University

2008

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Full-Text Articles in Physical Sciences and Mathematics

A Survey Of Transfer Learning Methods For Reinforcement Learning, Nicholas Bone Dec 2008

A Survey Of Transfer Learning Methods For Reinforcement Learning, Nicholas Bone

Computer Science Graduate and Undergraduate Student Scholarship

Transfer Learning (TL) is the branch of Machine Learning concerned with improving performance on a target task by leveraging knowledge from a related (and usually already learned) source task. TL is potentially applicable to any learning task, but in this survey we consider TL in a Reinforcement Learning (RL) context. TL is inspired by psychology; humans constantly apply previous knowledge to new tasks, but such transfer has traditionally been very difficult for—or ignored by—machine learning applications. The goals of TL are to facilitate faster and better learning of new tasks by applying past experience where appropriate, and to enable autonomous …


Fixing The Leaky Pipe: Increasing Recruitment Of Underrepresented Groups In Ecology, Brian L. Bingham, Lisette E. Torres Dec 2008

Fixing The Leaky Pipe: Increasing Recruitment Of Underrepresented Groups In Ecology, Brian L. Bingham, Lisette E. Torres

Environmental Sciences Faculty and Staff Publications

Many students from underrepresented groups lack adequate opportunities and mentorship as they head through the “pipeline” to graduate school. Despite the need for unique perspectives in collaborative scientific research, ethnic minority students continue to “leak” from the system. Here, I present some points for consideration for academic professionals (including educators, administrators, and program managers), based on the first-hand experiences of successful minority scientists.


Recent Extreme Avalanches: Triggered By Climate Change?, Christian Huggel, Jacqueline Caplan-Auerbach, Rick Wessels Nov 2008

Recent Extreme Avalanches: Triggered By Climate Change?, Christian Huggel, Jacqueline Caplan-Auerbach, Rick Wessels

Geology Faculty Publications

On 25 September 2008, seismo meters operated by the Alaska Volcano Observatory (AVO) registered strong ground shaking. On the basis of previous experience with such large seismic signals, AVO personnel were able to rapidly identify the seismic event as an avalanche. Two days later, an AVO overflight of Iliamna volcano, near Alaska's Cook Inlet, confirmed that a massive chunk of glacial ice and rock had broken free from its position on the upper flanks of the volcano, generating a massive avalanche that could have buried an entire town had it occurred in a more populated area.

Rapidly moving rock, ice, …


The Planet, 2008, Fall, Emily A. Linroth, Huxley College Of The Environment, Western Washington University Oct 2008

The Planet, 2008, Fall, Emily A. Linroth, Huxley College Of The Environment, Western Washington University

The Planet

No abstract provided.


Lake Samish Water Monitoring Project 2008 Final Report, Robin A. Matthews, Joan Vandersypen Sep 2008

Lake Samish Water Monitoring Project 2008 Final Report, Robin A. Matthews, Joan Vandersypen

Lake Samish

This report is a revised version of the 2006 and 2007 Final Reports by Matthews, et al., and contains most of the original text, updated figures, and additional discussion of all data collected from June 2005 through July 2008.

Lake Samish is a valuable aquatic resource, providing public access for boating, fishing, swimming, picnicking, and other water and lakeshore activities. Residents around the lake enjoy outstanding views of both the lake and its surrounding watershed, and the lake serves as a water supply for many of the lakeshore residents. Lake Samish is located in the Washington State Department of Ecology’s …


Molecular Nanoscience And Engineering On Surfaces, Willi Auwarter, Agustin Schiffrin, Alexander Weber-Bargioni, Yan Pennec, Andreas Riemann, Johannes V. Barth Sep 2008

Molecular Nanoscience And Engineering On Surfaces, Willi Auwarter, Agustin Schiffrin, Alexander Weber-Bargioni, Yan Pennec, Andreas Riemann, Johannes V. Barth

Physics & Astronomy

Molecular engineering of low-dimensional materials exploiting controlled self-assembly and positioning of individual atoms or molecules at surfaces opens up new pathways to control matter at the nanoscale. Our research thus focuses on the study of functional molecules and supramolecular architectures on metal substrates. As principal experimental tools we employ low-temperature scanning tunneling microscopy and spectroscopy. Here we review recent studies in our lab at UBC: Controlled manipulation of single CO molecules, self-assembled biomolecular nanogratings on Ag(111) and their use for electron confinement, as well as the organisation, conformation, metalation and electronic structure of adsorbed porphyrins.


Methane, Manganese, And Helium In Hydrothermal Plumes Following Volcanic Eruptions On The East Pacific Rise Near 9°500n, Brooke Love, Joseph A. (Joseph Anton) Resing, James P. Cowen, John E. Lupton, Daniel J. Fornari, Timothy M. (Timothy Mitchell) Shank, Dondra Biller Jun 2008

Methane, Manganese, And Helium In Hydrothermal Plumes Following Volcanic Eruptions On The East Pacific Rise Near 9°500n, Brooke Love, Joseph A. (Joseph Anton) Resing, James P. Cowen, John E. Lupton, Daniel J. Fornari, Timothy M. (Timothy Mitchell) Shank, Dondra Biller

Environmental Sciences Faculty and Staff Publications

As part of a rapid response cruise in May 2006, we surveyed water column hydrothermal plumes and bottom conditions on the East Pacific Rise between 9°46.0'N and 9°57.6'N, where recent seafloor volcanic activity was suspected. Real-time measurements included temperature, light transmission, and salinity. Samples of the plume waters were analyzed for methane, manganese, helium concentrations, and the δ13C of methane. These data allow us to examine the effects of the 2005–2006 volcanic eruption(s) on plume chemistry. Methane and manganese are sensitive tracers of hydrothermal plumes, and both were present in high concentrations. Methane reached 347 nM in upper …


Lake Whatcom Monitoring Project 2006/2007 Report, Robin A. Matthews, Michael Hilles, Joan Vandersypen, Robert J. Mitchell, Geoffrey B. Matthews Apr 2008

Lake Whatcom Monitoring Project 2006/2007 Report, Robin A. Matthews, Michael Hilles, Joan Vandersypen, Robert J. Mitchell, Geoffrey B. Matthews

Lake Whatcom Annual Reports

This report is part of an on-going series of annual reports and special project reports that document the Lake Whatcom monitoring program. This work is conducted by the Institute for Watershed Studies and other departments at Western Washington University.

The major objective of this program is to provide long-term baseline water quality monitoring in Lake Whatcom and selected tributaries. Each section contains brief explanations about the water quality data, along with discussions of patterns observed in Lake Whatcom.


The Planet, 2008, Spring, Page A. Buono, Huxley College Of The Environment, Western Washington University Apr 2008

The Planet, 2008, Spring, Page A. Buono, Huxley College Of The Environment, Western Washington University

The Planet

No abstract provided.


On Isoconcentration Surfaces Of Three Dimensional Turing Patterns, Tilmann Glimm, H. George E. Hentschel Feb 2008

On Isoconcentration Surfaces Of Three Dimensional Turing Patterns, Tilmann Glimm, H. George E. Hentschel

Mathematics Faculty Publications

We consider three-dimensional Turing patterns and their isoconcentration surfaces corresponding to the equilibrium concentration of the reaction kinetics. We call these surfaces equilibrium concentration surfaces (EC surfaces). They are the interfaces between the regions of "high" and "low" concentrations in Turing patterns. We give alternate characterizations of EC surfaces by means of two variational principles, one of them being that they are optimal for diffusive transport. Several examples of EC surfaces are considered. Remarkably, they are often very well approximated by certain minimal surfaces. We give a dynamical explanation for the emergence of Scherk's surface in certain cases, a structure …


The Morphostatic Limit For A Model Of Skeletal Pattern Formation In The Vertebrate Limb, Mark Alber, Tilmann Glimm, H. George E. Hentschel, Bogdan Kazmierczak, Yong-Tao Zhang, Jianfeng Zhu, Stuart (Stuart A.) Newman Feb 2008

The Morphostatic Limit For A Model Of Skeletal Pattern Formation In The Vertebrate Limb, Mark Alber, Tilmann Glimm, H. George E. Hentschel, Bogdan Kazmierczak, Yong-Tao Zhang, Jianfeng Zhu, Stuart (Stuart A.) Newman

Mathematics Faculty Publications

A recently proposed mathematical model of a “core” set of cellular and molecular interactions present in the developing vertebrate limb was shown to exhibit pattern-forming instabilities and limb skeleton-like patterns under certain restrictive conditions, suggesting that it may authentically represent the underlying embryonic process (Hentschel et al., Proc. R. Soc. B 271, 1713–1722,2004). The model, an eight-equation system of partial differential equations, incorporates the behavior of mesenchymal cells as “reactors,” both participating in the generation of morphogen patterns and changing their state and position in response to them. The full system, which has smooth solutions that exist globally …


Student Understanding Of Control Of Variables: Deciding Whether Or Not A Variable Influences The Behavior Of A System, Andrew Boudreaux, Peter S. Shaffer, Paula R. L. Heron, Lillian C. Mcdermott Feb 2008

Student Understanding Of Control Of Variables: Deciding Whether Or Not A Variable Influences The Behavior Of A System, Andrew Boudreaux, Peter S. Shaffer, Paula R. L. Heron, Lillian C. Mcdermott

Physics & Astronomy

The ability of adult students to reason on the basis of the control of variables was the subject of an extended investigation. This paper describes the part of the study that focused on the reasoning required to decide whether or not a given variable influences the behavior of a system. The participants were undergraduates taking introductory Physics and K-8 teachers studying physics and physical science in inservice institutes and workshops. Although most of the students recognized the need to control variables, many had significant difficulty with the underlying reasoning. The results indicate serious shortcomings in the preparation of future scientists …


Estimating Live Forest Carbon Dynamics With A Landsat-Based Curve-Fitting Approach, David O. Wallin, Todd A. Schroeder, Andrew N. Gray, Mark E. Harmon, Warren B. Cohen Jan 2008

Estimating Live Forest Carbon Dynamics With A Landsat-Based Curve-Fitting Approach, David O. Wallin, Todd A. Schroeder, Andrew N. Gray, Mark E. Harmon, Warren B. Cohen

Environmental Sciences Faculty and Staff Publications

Direct estimation of aboveground biomass with spectral reflectance data has proven challenging for high biomass forests of the Pacific Northwestern United States. We present an alternative modeling strategy which uses Landsat’s spatial, spectral and temporal characteristics to predict live forest carbon through integration of stand age and site index maps and locally calibrated Chapman-Richards curves. Predictions from the curve-fit model were evaluated at the local and landscape scales using two periods of field inventory data. At the pixel-level, the curve-fit model had large positive bias statistics and at the landscape scale over-predicted study area carbon for both inventory periods. Despite …


Finding Nash Equilibria In Two-Player, Zero Sum Games, Jeffrey Wimpee Jan 2008

Finding Nash Equilibria In Two-Player, Zero Sum Games, Jeffrey Wimpee

Computer Science Graduate and Undergraduate Student Scholarship

In many games, it is desirable to find strategies for all players that simultaneously maximize their respective worst-case payoffs. A set of strategies satisfying this criterion is called a Nash equilibrium. Because the search space of possible strategies grows rapidly as the size of the game increases, specialized algorithms are needed to efficiently find Nash equilibria. In this paper, current equilibrium-finding methods are presented and key areas for future work are identified. The first algorithm, due to Koller, Megiddo, and von Stengel, computes standard Nash equilibria in two-player, zero-sum games. The second algorithm, due to Miltersen and Sorensen, extends the …


Machine Vision: A Survey, David Phillips Jan 2008

Machine Vision: A Survey, David Phillips

Computer Science Graduate and Undergraduate Student Scholarship

This paper surveys the field of machine vision from a computer science perspective. It is written to act as an introduction to the field and presents the reader with references to specific implementations. Machine vision is a complex and developing field that can be broken into the three stages: stereo correspondence, scene reconstruction, and object recognition. We present the techniques and general approaches to each of these stages and summarize the future direction of research.


Information Extraction In Text Mining, Matt Mulins Jan 2008

Information Extraction In Text Mining, Matt Mulins

Computer Science Graduate and Undergraduate Student Scholarship

Text mining’s goal, simply put, is to derive information from text. Using multitudes of technologies from overlapping fields like Data Mining and Natural Language Processing we can yield knowledge from our text and facilitate other processing. Information Extraction (IE) plays a large part in text mining when we need to extract this data. In this survey we concern ourselves with general methods borrowed from other fields, with lower-level NLP techniques, IE methods, text representation models, and categorization techniques, and with specific implementations of some of these methods. Finally, with our new understanding of the field we can discuss a proposal …


Developing Web Crawlers For Vertical Search Engines: A Survey Of The Current Research, Pedro Huitema Jan 2008

Developing Web Crawlers For Vertical Search Engines: A Survey Of The Current Research, Pedro Huitema

Computer Science Graduate and Undergraduate Student Scholarship

Vertical search engines allow users to query for information within a subset of documents relevant to a pre-determined topic (Chakrabarti, 1999). One challenging aspect to deploying a vertical search engine is building a Web crawler that distinguishes relevant documents from non-relevant documents. In this research, we describe and analyze various methods to crawl relevant documents for vertical search engines, and we examine ways to apply these methods to building a local search engine. In a typical crawl cycle for a vertical search engine, the crawler grabs a URL from the URL frontier, downloads content from the URL, and determines the …


Combined Object Recognition Approaches For Mobile Robotics, Rusty Gerard Jan 2008

Combined Object Recognition Approaches For Mobile Robotics, Rusty Gerard

Computer Science Graduate and Undergraduate Student Scholarship

There are numerous solutions to simple object recognition problems when the machine is operating under strict environmental conditions (such as lighting). Object recognition in real-world environments poses greater difficulty however. Ideally mobile robots will function in real-world environments without the aid of fiduciary identifiers. More robust methods are therefore needed to perform object recognition reliably. A combined approach of multiple techniques improves recognition results. Active vision and peripheral-foveal vision—systems that are designed to improve the information gathered for the purposes of object recognition—are examined. In addition to active vision and peripheral-foveal vision, five object recognition methods that either make use …


Connectivity Of A Gaussian Network, Paul Balister, BéLa Bollobás, Amites Sarkar, Mark Walters Jan 2008

Connectivity Of A Gaussian Network, Paul Balister, BéLa Bollobás, Amites Sarkar, Mark Walters

Mathematics Faculty Publications

Following Etherington, Hoge and Parkes, we consider a network consisting of (approximately) N transceivers in the plane R² distributed randomly with density given by a Gaussian distribution about the origin, and assume each transceiver can communicate with all other transceivers within distance s. We give bounds for the distance from the origin to the furthest transceiver connected to the origin, and that of the closest transceiver that is not connected to the origin.


Comparison Of Marker-Based Pairwise Relatedness Estimators On A Pedigreed Plant Population, Amy D. Anderson, Marco C.A.M. Bink, W. Eric Van De Weg, Elizabeth A. Thompson Jan 2008

Comparison Of Marker-Based Pairwise Relatedness Estimators On A Pedigreed Plant Population, Amy D. Anderson, Marco C.A.M. Bink, W. Eric Van De Weg, Elizabeth A. Thompson

Mathematics Faculty Publications

Several estimators have been proposed that use molecular marker data to infer the degree of relatedness for pairs of individuals. The objective of this study was to evaluate the performance of seven estimators when applied to marker data of a set of 33 key individuals from a large complex apple pedigree. The evaluation considered different scenarios of allele frequencies and different numbers of marker loci. The method of moments estimators were Similarity, Queller-Goodknight, Lynch-Ritland and Wang. The maximum likelihood estimators were Thompson, Anderson-Weir and Jacquard. The pedigree-based coancestry coefficients were taken as the point of reference in calculating correlations and …


Rank Generating Functions As Weakly Holomorphic Modular Forms, Scott Ahlgren, Stephanie Treneer Jan 2008

Rank Generating Functions As Weakly Holomorphic Modular Forms, Scott Ahlgren, Stephanie Treneer

Mathematics Faculty Publications

Introduction and statement of results. Recent works have illustrated that the Fourier coefficients of harmonic weak Maass forms of weight 1/2 contain a wealth of number-theoretic and combinatorial information. After these works, it is known that many enigmatic q-series (the “mock theta functions” of Ramanujan, and certain rank-generating functions from the theory of partitions, for example) arise naturally as the “holomorphic parts” of such forms. See, for example, Bringmann and Ono [5, 6], Bringmann, Ono, and Rhoades [7], Zwegers [19], Bringmann and Lovejoy [4], Lovejoy and Osburn [12], or see the survey paper [13] for an overview. As another …


The Planet, 2008, Winter, Page A. Buono, Huxley College Of The Environment, Western Washington University Jan 2008

The Planet, 2008, Winter, Page A. Buono, Huxley College Of The Environment, Western Washington University

The Planet

No abstract provided.


Habitat Relationships And Gene Flow Of Martes Americana In Northern Idaho, Tzeidle N. (Tzeidle Nichole) Wasserman Jan 2008

Habitat Relationships And Gene Flow Of Martes Americana In Northern Idaho, Tzeidle N. (Tzeidle Nichole) Wasserman

WWU Graduate School Collection

Forest fragmentation can have a dramatic effect on landscape connectivity and dispersal of animals, potentially reducing gene flow within and among populations. American marten populations (Martes americana) are sensitive to forest fragmentation and the spatial configuration of patches of remnant mature forest has an important impact on habitat quality. This study represents an extensive multiple scale habitat relationships analysis conducted for American marten. In conjunction with Idaho Department of Fish and Game (IDFG) and the U.S. Forest Service, genetic data on marten populations across the Idaho Panhandle National Forest was used to build habitat relationships models. Over 3 years of …


An Investigation Of The Magnetic Fabrics And The Paleomagnetism Of The Ghost Rocks Formation, Kodiak Islands, Alaska, Sean F. Gallen Jan 2008

An Investigation Of The Magnetic Fabrics And The Paleomagnetism Of The Ghost Rocks Formation, Kodiak Islands, Alaska, Sean F. Gallen

WWU Graduate School Collection

Recent tectonic models based on the hypothesized existence of the Resurrection plate between the Kula and Farallon plates have questioned the location(s) of trench-ridge-trench (TRT) triple junction(s) along the Northern Cordilleran margin during Paleocene to Eocene time. The Paleocene Ghost Rocks Formation, located in the Kodiak islands, Alaska (latitude ~57°N), consists of pillow lavas and hypabyssal sills interbedded with turbidites, and is interpreted to have formed in a trench slope or slope basin during the passage of a TRT triple junction. A previous paleomagnetic study (Plumley et al., 1983) on the volcanic flows of the Ghost Rocks Formation suggests these …


Revisiting The Seven Devils-Wrangellia Connection: The Paleogeography Of Triassic Rocks In Western Idaho., Michael Liam. Kalk Jan 2008

Revisiting The Seven Devils-Wrangellia Connection: The Paleogeography Of Triassic Rocks In Western Idaho., Michael Liam. Kalk

WWU Graduate School Collection

The origins of and relationships between allochthonous terranes located west of the 87Sr/86Sr 0.706 line (Armstrong et al., 1977) have profound implications for understanding the Mesozoic paleogeography of western North America. The Wallowa- Seven Devils terrane has long been associated with Wrangellia, whose fragments can now be found in British Columbia, Canada and Alaska. However, stratigraphic, fossil, geochemical, structural, and paleomagnetic evidence linking the Wallowa-Seven Devils terrane to Wrangellia is considered equivocal (Follo, 1992). A new paleomagnetic study of the Seven Devils terrane may yield better results than Hillhouse et al. (1982) and, in conjunction with other …


A Spatially Explicit Relative Elevation Model For Padilla Bay, Washington, Peter Kairis Jan 2008

A Spatially Explicit Relative Elevation Model For Padilla Bay, Washington, Peter Kairis

WWU Graduate School Collection

The dynamics that govern the elevation of a coastal wetland relative to sea level are complex, involving non-linear feedbacks among opposing processes. Changes in the balance between these processes can result in significant alterations to vegetation communities that are adapted to a specific range of water levels. Given that the accretion rate in Padilla Bay, Washington, is suspected to be considerably lower than historical levels and that eustatic sea level rise continues to accelerate, the long term sustainability of the Zostera marina (eelgrass) meadows in the bay may be at risk to eventual submergence. I extended an existing Relative Elevation …


Timing And Nature Of Post-Collapse Sedimentation In Kulshan Caldera, North Cascades, Washington, Dennis M. (Dennis Martin) Feeney Jan 2008

Timing And Nature Of Post-Collapse Sedimentation In Kulshan Caldera, North Cascades, Washington, Dennis M. (Dennis Martin) Feeney

WWU Graduate School Collection

Sedimentary rocks found in the 4.5 x 8 km Kulshan caldera of the Mount Baker volcanic field in the North Cascades, WA, indicate that the post-collapse basin hosted a lacustrine environment shortly after the initial collapse at 1.149 Ma (Hildreth, 1996). The sedimentary rocks of the 14 Goat area in Kulshan caldera are well-preserved in 124 meters of stratigraphic exposure. Blocks of wall rock debris in the lower stratigraphy show instability in the caldera wall. Intermediate and late stages are mainly turbidites composed primarily of sediments derived from extra-caldera ignimbrite. From these 1 interpret the 14 Goat area of Kulshan …


Characterizing Surface Deformation From 1981 To 2007 On Mount Baker Volcano, Washington, Brendan E. Hodge Jan 2008

Characterizing Surface Deformation From 1981 To 2007 On Mount Baker Volcano, Washington, Brendan E. Hodge

WWU Graduate School Collection

Surface deformation studies at active volcanoes are used to detect changes to magmatic source regions beneath the volcano. At Mount Baker, Washington, continued elevated gas (CO2 and H2S) and heat flux from fumaroles in Sherman Crater indicate the presence of a degassing magma reservoir. Campaign geographic positioning system surveys in 2006 and 2007 provide slope distance measurements of all 19 trilateration lines on Mount Baker. These data are compared with previous slope distance measurements acquired in 1981 and 1983 with electronic distance measurement. The results indicate that surface deformation has occurred on Mount Baker during the last …


Kinematic Analysis Of Ductile Features Within The Northern Wenatchee Block, North Cascades, Washington, Gerald Griesel Jan 2008

Kinematic Analysis Of Ductile Features Within The Northern Wenatchee Block, North Cascades, Washington, Gerald Griesel

WWU Graduate School Collection

The Cascade crystalline core of Washington State is a block of high grade metamorphic and plutonic rocks at the southeast end of the Cretaceous-Tertiary Coast Plutonic Complex. Previous workers have debated whether northwest translation or southwest-vergent thrusting was responsible for regional metamorphism and deformation. The present study finds structural evidence supporting both orogen-normal and orogen-parallel displacements, thus indicating that the regional deformation can be broadly characterized as transpressional.

Units of the study area include: 1) the Napeequa schist, derived from an ocean floor protolith, and 2) an accreted Triassic arc, which includes the Marblemount Meta Quartz-Diorite (MMQD) and metamorphosed volcanic …


Magnetic Fabric Analysis Of Foreslope Sediments Of The Fraser River Delta, British Columbia, Andrew P. (Andrew Paul) Wiser Jan 2008

Magnetic Fabric Analysis Of Foreslope Sediments Of The Fraser River Delta, British Columbia, Andrew P. (Andrew Paul) Wiser

WWU Graduate School Collection

The results of a combined magnetic fabric and sedimentological investigation of trench and ridge structures along the foreslope of the Fraser Delta, British Columbia, indicate that turbidity currents are the likely origin of slope morphology. Evidence includes multiple and repetitive sequences of graded beds where trench and ridge structures are most pronounced and abundant. Distal to this region are fewer graded bedding sequences and increased evidence of hemipelagic deposition. A magnetic fabric analysis of cored sediments supports these conclusions. Stereographic projections of AMS ellipsoids from graded beds extracted from the mid-slope display characteristic turbidite relationships, whereas distal cores display hemipelagic …