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Bulletin: General Catalog Issue 2011-2012, Portland State University

Bulletin & Curriculum Change Documents

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Computational Approach To Dark Current Spectroscopy In Ccds As Complex Systems. Ii. Numerical Analysis Of The Uniqueness Parameters Evaluation, Ionel Tunaru, Ralf Widenhorn, Dan A. Iordache, Erik Bodegom

Physics Faculty Publications and Presentations

The evaluation of the uniqueness parameters of the temperature dependence in CCDs is difficult to the considerable number of input parameters and to the strongly nonlinear (exponential) theoretical relations. For this reason, the elaborated computer programs are very sensitive to the choice of the zero-order approximations of the effective (Si) energy gap, and of the weights associated to the experimentally determined dark current. The main goal of this work was to study the rather narrow stability domains of the zero-order approximations, which lead to attractors with physical meaning. It was found that the stability domains are surrounded by (usually in …

Nonlinear Time Dependence Of Dark Current In Charge-Coupled Devices, Justin Charles Dunlap, Erik Bodegom, Ralf Widenhorn

Physics Faculty Publications and Presentations

It is generally assumed that charge-coupled device (CCD) imagers produce a linear response of dark current versus exposure time except near saturation. We found a large number of pixels with nonlinear dark current response to exposure time to be present in two scientific CCD imagers. These pixels are found to exhibit distinguishable behavior with other analogous pixels and therefore can be characterized in groupings. Data from two Kodak CCD sensors are presented for exposure times from a few seconds up to two hours. Linear behavior is traditionally taken for granted when carrying out dark current correction and as a result, …

Analysis Of The Dpg Method For The Poisson Equation, Leszek Demkowicz, Jay Gopalakrishnan

Mathematics and Statistics Faculty Publications and Presentations

We give an error analysis of the recently developed DPG method applied to solve the Poisson equation and a convection-dffusion problem. We prove that the method is quasioptimal. Error estimates in terms of both the mesh size h and the polynomial degree p (for various element shapes) can be derived from our results. Results of extensive numerical experiments are also presented.

A Second Elasticity Element Using The Matrix Bubble, Jay Gopalakrishnan, Johnny Guzmán

Mathematics and Statistics Faculty Publications and Presentations

We presented a family of finite elements that use a polynomial space augmented by certain matrix bubbles in Cockburn et al. (2010) A new elasticity element made for enforcing weak stress symmetry. Math. Comput., 79, 1331–1349 . In this sequel we exhibit a second family of elements that use the same matrix bubble. This second element uses a stress space smaller than the first while maintaining the same space for rotations (which are the Lagrange multipliers corresponding to a weak symmetry constraint). The space of displacements is of one degree less than the first method. The analysis, while similar to …

Commuting Smoothed Projectors In Weighted Norms With An Application To Axisymmetric Maxwell Equations, Jay Gopalakrishnan, Minah Oh

Mathematics and Statistics Faculty Publications and Presentations

We construct finite element projectors that can be applied to functions with low regularity. These projectors are continuous in a weighted norm arising naturally when modeling devices with axial symmetry. They have important commuting diagram properties needed for finite element analysis. As an application, we use the projectors to prove quasioptimal convergence for the edge finite element approximation of the axisymmetric time-harmonic Maxwell equations on nonsmooth domains. Supplementary numerical investigations on convergence deterioration at high wavenumbers and near Maxwell eigenvalues and are also reported.

Symmetric Nonconforming Mixed Finite Elements For Linear Elasticity, Jay Gopalakrishnan, Johnny Guzmán

Mathematics and Statistics Faculty Publications and Presentations

We present a family of mixed methods for linear elasticity that yield exactly symmetric, but only weakly conforming, stress approximations. The method is presented in both two and three dimensions (on triangular and tetrahedral meshes). The method is efficiently implementable by hybridization. The degrees of freedom of the Lagrange multipliers, which approximate the displacements at the faces, solve a symmetric positive-definite system. The design and analysis of this method is motivated by a new set of unisolvent degrees of freedom for symmetric polynomial matrices. These new degrees of freedom are also used to give a new simple calculation of the …

Analysis Of Hdg Methods For Stokes Flow, Bernardo Cockburn, Jay Gopalakrishnan, Ngoc Cuong Nguyen, Jaume Peraire, Francisco-Javier Sayas

Mathematics and Statistics Faculty Publications and Presentations

In this paper, we analyze a hybridizable discontinuous Galerkin method for numerically solving the Stokes equations. The method uses polynomials of degree $ k$ for all the components of the approximate solution of the gradient-velocity-pressure formulation. The novelty of the analysis is the use of a new projection tailored to the very structure of the numerical traces of the method. It renders the analysis of the projection of the errors very concise and allows us to see that the projection of the error in the velocity superconverges. As a consequence, we prove that the approximations of the velocity gradient, the …

Balance Systems And The Variational Bicomplex, Serge Preston

Mathematics and Statistics Faculty Publications and Presentations

In this work we show that the systems of balance equations (balance systems) of continuum thermodynamics occupy a natural place in the variational bicomplex formalism. We apply the vertical homotopy decomposition to get a local splitting (in a convenient domain) of a general balance system as the sum of a Lagrangian part and a complemental "pure non-Lagrangian" balance system. In the case when derivatives of the dynamical fields do not enter the constitutive relations of the balance system, the "pure non-Lagrangian" systems coincide with the systems introduced by S. Godunov [Soviet Math. Dokl. 2 (1961), 947–948] and, later, asserted as …

Research Summary: Assessment, Robert Michael Capraro, Mary F. Roe, Micki M. Caskey, David Strahan, Penny A. Bishop, Christopher C. Weiss

Curriculum and Instruction Faculty Publications and Presentations

Assessment is important for middle level teachers and their students. In fact, the National Middle School Association (NMSA) highlighted curriculum, instruction, and assessment in This We Believe: Keys to Educating Young Adolescents (NMSA, 2010). The intention of this summary is to establish assessment’s rightful position as one priority for middle grade teachers and their students. When used wisely and well, teachers obtain information about their students’ strengths and needs, and their students remain informed about their achievements. To begin, educators need an operational definition of assessment. Based on the work of many scholars (e.g., Delclos, Vye, Burns, Bransford, & Hasselbring, …

Polynomial Extension Operators. Part Iii, Leszek Demkowicz, Jay Gopalakrishnan, Joachim Schöberl

Mathematics and Statistics Faculty Publications and Presentations

In this concluding part of a series of papers on tetrahedral polynomial extension operators, the existence of a polynomial extension operator in the Sobolev space H(div) is proven constructively. Specifically, on any tetrahedron K, given a function w on the boundary ∂K that is a polynomial on each face, the extension operator applied to w gives a vector function whose components are polynomials of at most the same degree in the tetrahedron. The vector function is an extension in the sense that the trace of its normal component on the boundary ∂K coincides with w. Furthermore, the extension operator is …

A Content Analysis Of The Strategic Plans Of The Coalition Of Urban Serving Universities' Academic Libraries, Thomas Bielavitz

Library Faculty and Staff Publications and Presentations

As academic libraries support the curricular mission of the university, the strategic plans of academic libraries often reflect the priorities and initiatives of the larger institution. Urban universities often incorporate concepts of community engagement in their mission. The Coalition of Urban Serving Universities (http://www.usucoalition.org), a federation of 43 urban universities, has developed initiatives which seek to establish the university and city as partners. Using the publicly-accessible strategic plans of the Coalition of Urban Serving Universities (USU) affiliated libraries as a data set, the research will perform a content analysis, using Atlas.ti software, to look for evidence that the libraries are …

Strategies For Labeling Proteins With Paracest Agents, Olga Vasalatiy, Piyu Zhao, Mark Woods, Andrei Marconescu, Aminta Castillo-Muzquiz, Philip Thorpe, Garry Kiefer, A. Dean Sherry

Chemistry Faculty Publications and Presentations

Reactive surface lysine groups on the chimeric monoclonal antibody (3G4) and on human serum albumin (HSA) were labeled with two different PARACEST chelates. Between 7.4 – 10.1 chelates were added per 3G4 molecule and between 5.6 – 5.9 chelates per molecule of HSA, depending upon which conjugation chemistry was used. The immunoreactivity of 3G4 as measured by ELISA assays was highly dependent upon the number of attached chelates: 88% immunoreactivity with 7.4 chelates per antibody versus only 17% immunoreactivity with 10.1 chelates per antibody. Upon conjugation to 3G4, the bound water lifetime of Eu-1 increased only marginally, up from …

Imaging The Extracellular Ph Of Tumors By Mri After Injection Of A Single Cocktail Of T1 And T2 Contrast Agents, Gary V. Martinez, Xiaomeng Zhang, María L. García-Martín, David L. Morse, Mark Woods, A. Dean Sherry, Robert J. Gillies

Chemistry Faculty Publications and Presentations

The extracellular pH (pH(e) ) of solid tumors is acidic, and there is evidence that an acidic pH(e) is related to invasiveness. Herein, we describe an MRI single-infusion method to measure pH(e) in gliomas using a cocktail of contrast agents (CAs). The cocktail contained gadolinium-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraaminophosphonate (GdDOTA-4AmP) and dysprosium-1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetrakis(methylenephosphonic acid) (DyDOTP), whose effects on relaxation are sensitive and insensitive to pH, respectively. The Gd-CA dominated the spin-lattice relaxivity ΔR(1) , whereas the Dy-CA dominated the spin-spin relaxivity ΔR(2)*. The ΔR(2)* effects were used to determine the pixel-wise concentration of [Dy] which, in turn, was used to calculate a value for [Gd] …

Detecting Specific Saccharides Via A Single Indicator, Soojin Lim, Jorge O. Escobedo, Mark Lowry, Robert M. Strongin

Chemistry Faculty Publications and Presentations

An improved synthesis of a rhodamine boronic acid indicator is reported. This compound is used in an optimized data collection protocol for wavelength- and time-dependent selectivity of sugars such as fructose and ribose derivatives. One indicator is thus used to selectively distinguish structurally related sugar analytes.

Can Salmonids (Oncorhynchus Spp.) Be Identified To Species Using Vertebral Morphometrics?, Harriet R. Huber, Jeffery C. Jorgensen, Virginia L. Butler, Greg Baker, Rebecca Stevens

Anthropology Faculty Publications and Presentations

Remains of anadromous Pacific salmon and trout (genus Oncorhynchus) are common in archaeological sites from California to Alaska; however, morphological similarity generally precludes species identification, limiting the range of questions that salmonid remains can address in relation to past human use and ongoing efforts in conservation biology. We developed a relatively simple, rapid, and non-destructive way to classify salmon and trout vertebrae from archaeological contexts to species using length, height and the ratio of length to height. Modern reference material was obtained from all seven anadromous Oncorhynchus species native to the west coast of North America. A minimum of ten …

Circulation, Sediment Concentration And Oxygen Depletion In The Tidal Ems River, Stefan A. Talke, Huib E. De Swart

Civil and Environmental Engineering Faculty Publications and Presentations

We present measurements which show that the tidal Ems River in Germ any is extremely muddy over a 30 km + turbid zone, with fluid mud o f 1-2 m thickness covering the bed with suspended sediment concentrations (SSC) o f greater than 50 kg.m^-3. Moreover, we show that these elevated SSC contain large quantities of organic material which deplete dissolved oxygen (DO) and produce summertime hypoxic zones. Using mathematical modeling, we develop simplified representations o f the estuary physics that reproduce the tidally-averaged circulation, SSC distribution, and oxygen depletion. These models show that SSC and oxygen concentrations …

Freight Distribution Problems In Congested Urban Areas: Fast And Effective Solution Procedures To Time-Dependent Vehicle Routing Problems, Miguel A. Figliozzi

Civil and Environmental Engineering Faculty Publications and Presentations

Congestion is a common phenomenon in all medium to large cities of the world. Reliability of freight movement in urban areas is an important issue to manufacturing or service companies whose operation is based in just-in-time approaches. These companies tend to provide high value or time sensitive products/services. As congestion increases, carriers face increasing challenges to satisfy their time sensitive customers in an economical way. Route designs or schedules which require long computation times or ignore travel time variations will result in inefficient and suboptimal solutions. Poorly designed routes that lead freight vehicles into congested arteries and streets not only …

Uncertainty Analysis Of A Low Flow Model For The Rhine River, Mehmet C. Demirel, Martijn Booij

Civil and Environmental Engineering Faculty Publications and Presentations

It is widely recognized that hydrological models are subject to parameter uncertainty. However, little attention has been paid so far to the uncertainty in parameters of the data-driven models like weights in neural networks. This study aims at applying a structured uncertainty analysis to a data-driven model for low flow forecasting with a lead time of 14 days in the Rhine River. In the modeling phase, the Rhine basin is divided into seven major sub-basins. Each sub-basin is modeled separately with a data-driven model and the output discharges were routed to Lobith with another data-driven model. Basin averaged precipitation, basin …

Improving The Characterization Of Initial Condition For Ensemble Streamflow Prediction Using Data Assimilation, Caleb Matthew Dechant, Hamid Moradkhani

Civil and Environmental Engineering Faculty Publications and Presentations

Within the National Weather Service River Forecast System, water supply forecasting is performed through Ensemble Streamflow Prediction (ESP). ESP relies both on the estimation of initial conditions and historically resampled forcing data to produce seasonal volumetric forecasts. In the western US, the accuracy of initial condition estimation is particularly important due to the large quantities of water stored in mountain snowpack. In order to improve the estimation of snow quantities, this study explores the use of ensemble data assimilation. Rather than relying entirely on the model to create single deterministic initial snow water storage, as currently implemented in operational forecasting, …

An Investigation On Fast And Frugal Model For New Project Screening, Antonie J. Jetter, Fatima M. Albar

Engineering and Technology Management Faculty Publications and Presentations

Research in psychology is increasingly interested in decision-makers' use of heuristics or rules of thumb because they have accuracies close to more complex decision rules and seem particularly useful in difficult decision-making contexts when uncertainty is high and speed is of the essence. One particularly difficult decision setting is the fuzzy front-end of new product development because a large number of product ideas need to be screened to identify the few that should be developed further. This process is currently poorly supported through decision tools and mainly occurs on the basis of managerial “gut-feel”. This study explores managerial “gut-feel” by …

Urban Water Demand Modeling: Review Of Concepts, Methods, And Organizing Principles, Heejun Chang, Lily House-Peters

Institute for Sustainable Solutions Publications and Presentations

In this paper, we use a theoretical framework of coupled human and natural systems to review the methodological advances in urban water demand modeling over the past 3 decades. The goal of this review is to quantify the capacity of increasingly complex modeling techniques to account for complex human and natural processes, uncertainty, and resilience across spatial and temporal scales. This review begins with coupled human and natural systems theory and situates urban water demand within this framework. The second section reviews urban water demand literature and summarizes methodological advances in relation to four central themes: (1) interactions within and …

Structuring Expert Input For A Knowledge-Based Approach To Watershed Condition Assessment For The Northwest Forest Plan, Usa, Sean N. Gordon, Kirsten Gallo

Institute for Sustainable Solutions Publications and Presentations

Assessments of watershed condition for aquatic and riparian species often have to rely on expert opinion because of the complexity of establishing statistical relationships among the many factors involved. Such expert-based assessments can be difficult to document and apply consistently over time and space. We describe and reflect on the process of developing a computer-based decision support application from expert judgments for assessing aquatic and riparian conditions over the 100,000 km2 managed by the US federal government under the Northwest Forest Plan. The decision support system helped structure and document the assessment process and provided consistency and transparency to the …

Sources And Pathways To The Environment And Environmental Presence, Tess Chadil

Environmental Science and Management Professional Master's Project Reports

In an attempt to successfully address and reduce contamination from toxic chemicals and other pollutants in the Oregon environment, the Oregon Department of Environmental Quality is in the early stages of developing a comprehensive agency-wide toxics reduction plan. The plan seeks to find a more efficient, sustainable approach to addressing contaminants of concern to human and ecological health. Team Toxics, a work group compromised of members from various DEQ departments, has been created to collaborate and create the framework for developing these strategies. In summer 2009, Team Toxics was in the very early stages of development, and found the need …

No More Freeways: Urban Land Use-Transportation Dynamics Without Freeway Capacity Expansion, Lei Zhang, We Xu

TREC Final Reports

Observations of the various limitations of freeway capacity expansion have led to a provocative planning and policy question – What if we completely stop building additional freeway capacity. From a theoretical perspective, as a freeway transportation network matures, there exists a saturation point beyond which any additional freeway capacity would only be counterproductive from a welfare point of view, and worsen the existing urban transportation problems. Traditional benefit/cost analysis of individual freeway capacity expansion projects often ignores long-term induced demand and land use changes and does not represent a systems approach to this important theoretical issue. From a practical perspective, …

Personal Knowledge And The Inner Sciences, Martin Zwick

Complex Systems Faculty Publications and Presentations

This paper conceptualizes spiritual disciplines as sciences. It uses this conceptualization to probe into the similarities and differences between modern science and religious tradition, and into the cultural significance and possible future impact of the “new religions”. The paper draws upon the ideas of Michael Polanyi as a possible bridge between science and religion, and proposes that these ideas are relevant not only to the major Western religions, but to Eastern and non-mainstream Western religions as well. Imagining science as a spiritual path, or gnosis, would challenge an exclusivist understanding of scientific knowledge, and suggest the relevance of such knowledge …

System Dynamics Modeling As A Potentially Useful Tool In Analyzing Mitigation Strategies To Reduce Overdose Deaths Associated With Pharmaceutical Opioid Treatment Of Chronic Pain, Wayne Wakeland, Teresa D. Schmidt, Aaron Gilson, J. David Haddox, Lynn Webster

Complex Systems Faculty Publications and Presentations

Objective. To illustrate a system-level, simulationbased approach for evaluating mitigation strategies to address the dramatic rise in abuse, addiction, and overdose deaths associated with the use of pharmaceutical opioid analgesics to treat chronic pain.

Simulated Interventions. Making available drug formulations with increased tamper-resistance, prescriber education programs, and programs that reduce rates of medical user-related abuse and addiction.

Simulated Outcome Measure. Number of overdose deaths of medical users of pharmaceutical opioid analgesics, including those who abuse or have become addicted.

Methods. A demonstration system dynamics model is developed, tested, and used to evaluate the impact of candidate mitigation strategies on the …

The Obvious Invisibility Of The Relationship Between Technology And Social Values, Jamie P. Ross

Women, Gender, and Sexuality Studies Faculty Publications and Presentations

We all too often assume that technology is the product of objective scientific research and that technology’s moral value lies in only the moral character of its user. To remove technology from a moral realm, we assume value and context neutrality. Yet the power of technology is a reflection of the values that exist in its developmental context. Technology’s moral realm is visible in the reciprocal relationship between culture and technology in the epidemiology of AIDS, clinical research and practice regarding heart disease, and DNA research. Cultural values decide what counts as a scientific question. When we look at the …

(Editorial) A Long Term View Of Rare Plant Reintroduction. A Response To Godefroid Et Al. 2011: How Successful Are Plant Reintroductions?, Matthew A. Albrecht, Edward O. Guerrant Jr., Joyce Maschinski, Kathryn Kennedy

Environmental Science and Management Faculty Publications and Presentations

This is an editorial response to Godefroidet al. (2011). How successful are plant species reintroductions? Biological Conservation 144, 672-682.

The Sociology Of Landowner Interest In Restoring Fire-Adapted, Biodiverse Habitats In The Wildland-Urban Interface Of Oregon's Willamette Valley Ecoregion, Max Nielsen-Pincus

Environmental Science and Management Faculty Publications and Presentations

In many parts of the world, the combined effects of wildfire, climate change, and population growth in the wildland-urban interface pose increasing risks to both people and biodiversity. These risks are exemplified in western Oregon’s Willamette Valley Ecoregion, where population is projected to double by 2050 and climate change is expected to increase wildfire risk. Restoring elements of the region’s historic fire-adapted prairie, savanna, and woodland habitats may help to reduce future wildfire risk and help conserve the region’s threatened biodiversity. We report on a mail survey (n = 939) examining the socio-demographic factors influencing private landowners’ likelihood of restoring …