Physical Sciences and Mathematics Commons^™

Infrared Radiography: Modeling X-Ray Imaging Without Harmful Radiation, Otto Zietz, Elliot E. Mylott, Ralf Widenhorn

Physics Faculty Publications and Presentations

Planar x-ray imaging is a ubiquitous diagnostic tool and is routinely performed to diagnose conditions as varied as bone fractures and pneumonia. The underlying principle is that the varying attenuation coefficients of air, water, tissue, bone, or metal implants within the body result in non-uniform transmission of x-ray radiation. Through the detection of transmitted radiation, the spatial organization and composition of materials in the body can be ascertained. In this paper, we describe an original apparatus that teaches these concepts by utilizing near infrared radiation and an up-converting phosphorescent screen to safely probe the contents of an opaque enclosure.

History, Current Conditions, And Wetland Restoration At Killin Wetlands Natural Area, Washington County, Oregon, John A. Christy

Institute for Natural Resources Publications

In September 2014, the Metro Natural Area Program engaged The Wetland Conservancy to develop a scientific assessment of Metro’s 590-acre Killin Wetlands Natural Area. Metro acquired the lands comprising the KWNA between 2000 and 2012 with funds from two voterapproved open space bond measures. Since 2000, Metro has sought to advance natural area restoration at the site, focusing on the suppression of non-native pasture weeds and planting of native trees and shrubs in higher parts of the floodplain and its edges. Most uplands in Metro ownership have been maintained in agriculture through leased partnerships with local farmers.

Metro and its …

Query From Examples: An Iterative, Data-Driven Approach To Query Construction, Hao Li, Chee-Yong Chan, David Maier

Computer Science Faculty Publications and Presentations

In this paper, we propose a new approach, called Query from Examples (QFE), to help non-expert database users construct SQL queries. Our approach, which is designed for users who might be unfamiliar with SQL, only requires that the user is able to determine whether a given output table is the result of his or her intended query on a given input database. To kick-start the construction of a target query Q, the user first provides a pair of inputs: a sample database D and an output table R which is the result of Q on D. As there will be …

The Effects Of Global Change Upon United States Air Quality, Rodrigo Gonzalez-Abraham, Serena H. Chung, Jeremy C. Avise, Brian Lamb, Eric P. Salathé Jr., Christopher G. Nolte, Dan Loughlin, Alex Guenther, Christine Wiedinmyer, Tiffany Duhl, Yang Zhang, David G. Streets

Civil and Environmental Engineering Faculty Publications and Presentations

To understand more fully the effects of global changes on ambient concentrations of ozone and particulate matter with aerodynamic diameter smaller than 2.5 μm (PM_2.5) in the United States (US), we conducted a comprehensive modeling effort to evaluate explicitly the effects of changes in climate, biogenic emissions, land use and global/regional anthropogenic emissions on ozone and PM_2.5 concentrations and composition. Results from the ECHAM5 global climate model driven with the A1B emission scenario from the Intergovernmental Panel on Climate Change (IPCC) were downscaled using the Weather Research and Forecasting (WRF) model to provide regional meteorological fields. We …

Controlled Deposition Of Tin Oxide And Silver Nanoparticles Using Microcontact Printing, Joo C. Chan, Nicole Hannah-Moore, Shankar B. Rananavare

Chemistry Faculty Publications and Presentations

This report describes extensive studies of deposition processes involving tin oxide (SnO_x) nanoparticles on smooth glass surfaces. We demonstrate the use of smooth films of these nanoparticles as a platform for spatially-selective electroless deposition of silver by soft lithographic stamping. The edge and height roughness of the depositing metallic films are 100 nm and 20 nm, respectively, controlled by the intrinsic size of the nanoparticles. Mixtures of alcohols as capping agents provide further control over the size and shape of nanoparticles clusters. The distribution of cluster heights obtained by atomic force microscopy (AFM) is modeled through a modified …

Phthalimide-Based Π-Conjugated Small Molecules With Tailored Electronic Energy Levels For Use As Acceptors In Organic Solar Cells, Arthur D. Hendsbee, Seth M. Mcafee, Jon-Paul Sun, Theresa M. Mccormick, Ian G. Hill, Gregory C. Welch

Chemistry Faculty Publications and Presentations

The design, synthesis, and characterization of seven phthalimide-based organic π-conjugated small molecules are reported. The new materials are based on a phthalimide–thiophene–CORE–thiophene–phthalimide architecture. The CORE units utilized were phthalimide (M2), diketopyrrolopyrrole (M3), isoindigo (M4), naphthalene diimide (M5), perylene diimide (M6), and difluorobenzothiadiazole (M7); they were specifically selected to progressively increase the electron affinity of the resulting compound. A small molecule with no core (M1) was synthesized for comparison. Each material was synthesized through optimized direct heteroarylation cross-coupling procedures using bench top solvents in air. Combinations of …

Robust Estimates For Hp-Adaptive Approximations Of Non-Self-Adjoint Eigenvalue Problems, Stefano Giani, Luka Grubišić, Agnieszka Międlar, Jeffrey S. Ovall

Mathematics and Statistics Faculty Publications and Presentations

We present new residual estimates based on Kato’s square root theorem for spectral approximations of non-self-adjoint differential operators of convection–diffusion–reaction type. These estimates are incorporated as part of an hp-adaptive finite element algorithm for practical spectral computations, where it is shown that the resulting a posteriori error estimates are reliable. Provided experiments demonstrate the efficiency and reliability of our approach.

Mathematical Model For Bone Mineralization, Svetlana V. Komarova, Lee Safranek, Jay Gopalakrishnan, Miao-Jung Yvonne Ou, Marc D. Mckee, Monzur Murshed, Frank Rauch, Erica Zuhr

Mathematics and Statistics Faculty Publications and Presentations

Defective bone mineralization has serious clinical manifestations, including deformities and fractures, but the regulation of this extracellular process is not fully understood. We have developed a mathematical model consisting of ordinary differential equations that describe collagen maturation, production and degradation of inhibitors, and mineral nucleation and growth. We examined the roles of individual processes in generating normal and abnormal mineralization patterns characterized using two outcome measures: mineralization lag time and degree of mineralization. Model parameters describing the formation of hydroxyapatite mineral on the nucleating centers most potently affected the degree of mineralization, while the parameters describing inhibitor homeostasis most effectively …

Stability Of A Circular System With Multiple Asymmetric Laplacians, Ivo Herman, Dan Martinec, J. J. P. Veerman, Michael Sebek

Mathematics and Statistics Faculty Publications and Presentations

We consider an asymptotic stability of a circular system where the coupling Laplacians are different for each state used for synchronization. It is shown that there must be a symmetric coupling in the output state to guarantee the stability for agents with two integrators in the open loop. Systems with agents having three or more integrators cannot be stabilized by any coupling. In addition, recent works in analysis of a scaling in vehicular platoons relate the asymptotic stability of a circular system to a string stability. Therefore, as confirmed by simulations in the paper, our results have an application also …

Periodic State Revivals In Commensurate Waveguide Arrays, Jovan Petrovic, J. J. P. Veerman

Mathematics and Statistics Faculty Publications and Presentations

Emerging optical and quantum computers require hardware capable of coherent transport of and operations on quantum states. Here, we investigate finite optical waveguide arrays with linear coupling as means of efficient and compact coherent state transfer. Coherent transfer with periodic state revivals is enabled by engineering coupling coefficients between neighbouring waveguides to yield commensurate eigenvalue spectrum. Particular cases of finite arrays have been actively studied to achieve the perfect state transfer by mirroring the input into the output state.

We explore a much wider scope of coherent propagation and revivals of both the state amplitude and phase. We analytically solve …

Self-Reported Experiences Of Climate Change In Nigeria: The Role Of Personal And Socio-Environmental, Idowu Ajibade, Frederick Ato Armah, Vincent Kuuire, Isaac Luginaah, Gordon Mcbean

Geography Faculty Publications and Presentations

In this study, we examined the individual and socio-environmental factors that mediate differential self-reported experiences of climate change in coastal communities in Lagos, Nigeria. Binary complementary log-log multivariate regression was used to model residents’ experiences of changing rainfall patterns, ocean surges, and flood events. An analysis of both compositional and contextual factors showed that there were urban communities where vulnerability to flooding tends to be clustered, and that this was not fully explained by the characteristics of the people of whom the community was composed. This study, thus, underscores the importance and complex nature of the interaction between personal and …

Discourses Of Deflection: The Politics Of Framing China’S South North Water Transfer Project, Britt Crow-Miller

Geography Faculty Publications and Presentations

Despite significant financial, ecological and social trade-offs, China has moved forward with constructing and operationalising the world’s largest interbasin water transfer project to date, the South-North Water Transfer Project (SNWTP). While it is fundamentally linked to broader political-economic goals within the context of China’s post-Mao development agenda, the SNWTP is frequently discussed in apolitical terms. Based on extensive discourse analysis and interviews with government officials across North China, I argue that the Chinese government is using "discourses of deflection" to present the project as politically neutral in order to serve its ultimate goal of maintaining the high economic growth rates …

Default Rules In Functional Logic Programs, Sergio Antoy, Michael Hanus

Computer Science Faculty Publications and Presentations

In functional logic programs, rules are applicable independently of textual order, i.e., any rule can potentially be used to evaluate an expression. This is similar to logic languages and opposite to functional languages, e.g., Haskell enforces a strict sequential interpretation of rules. However, in some situations it is convenient to express alternatives by means of compact default rules. Although default rules are often used in functional programs, the non-deterministic nature of functional logic programs does not allow to directly transfer this concept from functional to functional logic languages in a meaningful way. In this paper we propose a new concept …

Needed Computations Shortcutting Needed Steps, Sergio Antoy, Jacob Johannsen, Steven Libby

Computer Science Faculty Publications and Presentations

We define a compilation scheme for a constructor-based, strongly-sequential, graph rewriting system which shortcuts some needed steps. The object code is another constructor-based graph rewriting system. This system is normalizing for the original system when using an innermost strategy. Consequently, the object code can be easily implemented by eager functions in a variety of programming languages. We modify this object code in a way that avoids total or partial construction of the contracta of some needed steps of a computation. When computing normal forms in this way, both memory consumption and execution time are reduced compared to ordinary rewriting computations …

The Expression Problem, Gracefully, Andrew P. Black

Computer Science Faculty Publications and Presentations

The “Expression Problem” was brought to prominence by Wadler in 1998. It is widely regarded as illustrating that the two mainstream approaches to data abstraction — procedural abstraction and type abstraction— are complementary, with the strengths of one being the weaknesses of the other. Despite an extensive literature, the origin of the problem remains ill-understood. I show that the core problem is in fact the use of global constants, and demonstrate that an important aspect of the problem goes away when Java is replaced by a language like Grace, which eliminates them.

The Grace Programming Language Draft Specification Version 0.5. 2025, Andrew P. Black, Kim B. Bruce, James Noble

Computer Science Faculty Publications and Presentations

This is a specification of the Grace Programming Language. This specification is notably incomplete, and everything is subject to change. For discussion and rationale, see http://gracelang.org.

Ear-Phone: A Context-Aware Noise Mapping Using Smart Phones, Rajib Rana, Chun Tung Chou, Nirupama Bulusu, Salil Kanhere, Wen Hu

Computer Science Faculty Publications and Presentations

A noise map facilitates the monitoring of environmental noise pollution in urban areas. It can raise citizen awareness of noise pollution levels, and aid in the development of mitigation strategies to cope with the adverse effects. However, state-of-the-art techniques for rendering noise maps in urban areas are expensive and rarely updated (for months or even years), as they rely on population and traffic models rather than on real data. Smart phone based urban sensing can be leveraged to create an open and inexpensive platform for rendering up-to-date noise maps. In this paper, we present the design, implementation and performance evaluation …

Desiderata For A Big Data Language, David Maier

Computer Science Faculty Publications and Presentations

Data management and analytics systems for big data have proliferated, including column stores, array databases, graphanalysis environments and linear-algebra packages. This burgeoning of systems has lead to a surfeit of language and APIs. It is time to consider a new framework that can span these systems and simplify the programming and maintenance of Big Data applications. There are two key goals for such a framework:

Portability: It should be relatively easy to move an application or tool developed on one platform to operate against another. As a corollary, back-end data and analytics services should be swappable in a particular …

Usage Based Topology For Dcns, Qing Yi, Suresh Singh

Computer Science Faculty Publications and Presentations

Many data center network topologies are designed to provide full bisection bandwidth for tens of thousands of servers in order to achieve high network throughput and server agility. However, the utilization rate of DCNs on average is below 10%, which results in a significant waste of network resources and energy. Many researchers propose consolidating network traffic flows to maximize the set of idle network equipment and switching them to low power mode to save energy. In this paper, we propose using skinnier network topologies to meet performance requirements of realistic loads thus saving not only energy but capital cost as …

A Demonstration Of The Bigdawg Polystore System, Aaron J. Elmore, Jennie Duggan, Michael Stonebraker, Magdalena Balazinska, Ugur Cetintemel, Vijay Gadepally, J. Heer, Bill Howe, Jeremy Kepner, Tim Kraska, Samuel Madden, David Maier, Timothy G. Mattson, S. Papadopoulos, J. Parkhurst, Nesime Tatbul, Manasi Vartak, Stan Zdonik

Computer Science Faculty Publications and Presentations

This paper presents BigDAWG, a reference implementation of a new architecture for “Big Data” applications. Such applications not only call for large-scale analytics, but also for real-time streaming support, smaller analytics at interactive speeds, data visualization, and cross-storage-system queries. Guided by the principle that “one size does not fit all”, we build on top of a variety of storage engines, each designed for a specialized use case. To illustrate the promise of this approach, we demonstrate its effectiveness on a hospital application using data from an intensive care unit (ICU). This complex application serves the needs of doctors and researchers …

Demonstrating "Data Near Here": Scientific Data Search, Veronika Margaret Megler, David Maier

Computer Science Faculty Publications and Presentations

Prior work proposed "Data Near Here" (DNH), a data search engine for scientific archives that is modeled on Internet search engines. DNH performs a periodic, asynchronous scan of each dataset in an archive, extracting lightweight features that are combined to form a dataset summary. During a search, DNH assesses the similarity of the search terms to the summary features and returns to the user, at interactive timescales, a ranked list of datasets for further exploration and analysis. We will demonstrate the search capabilities and ancillary metadata-browsing features for an archive of observational oceanographic data. While comparing search terms to complete …

Effects Of Sex And Mycorrhizal Fungi On Gas Exchange In The Dioecious Salt Marsh Grass Distichlis Spicata, Kassandra Reuss-Schmidt, Todd N. Rosenstiel, Sally R. Rogers, Allie G. Simpson, Sarah M. Eppley

Biology Faculty Publications and Presentations

Premise of research. In dioecious plant species, males and females often differ in physiology, and mycorrhizal fungal relationships are likely to influence these differences. However, few data are available on the potential role of mycorrhizal fungi in altering sex-specific physiology and population sex ratios of dioecious plant species.

Methodology. In this study, we measured leaf gas exchange in a multifactorial greenhouse experiment with and without mycorrhizal fungal additions and under field conditions in Distichlis spicata, a dioecious C4 salt marsh grass, displaying extreme spatial sex ratio variation.

Pivotal results. We found a significant interaction between gas exchange, plant sex, and …

S-Store: Streaming Meets Transaction Processing, John Meehan, Nesime Tatbul, Cansu Aslantas, Ugur Cetintemel, Jiang Du, Tim Kraska, Samuel Madden, David Maier, Andrew Pavlo, Michael Stonebraker, Kristin A. Tufte, Hao Wang

Computer Science Faculty Publications and Presentations

Stream processing addresses the needs of real-time applications. Transaction processing addresses the coordination and safety of short atomic computations. Heretofore, these two modes of operation existed in separate, stove-piped systems. In this work, we attempt to fuse the two computational paradigms in a single system called S-Store. In this way, S-Store can simultaneously accommodate OLTP and streaming applications. We present a simple transaction model for streams that integrates seamlessly with a traditional OLTP system. We chose to build S-Store as an extension of H-Store, an open-source, in-memory, distributed OLTP database system. By implementing S-Store in this way, we can make …

A Theory Of Name Resolution, Pierre Néron, Andrew Tolmach, Eelco Visser, Guido Wachsmuth

Computer Science Faculty Publications and Presentations

We describe a language-independent theory for name binding and resolution, suitable for programming languages with complex scoping rules including both lexical scoping and modules. We formulate name resolution as a two-stage problem. First a language-independent scope graph is constructed using language-specific rules from an abstract syntax tree. Then references in the scope graph are resolved to corresponding declarations using a language-independent resolution process. We introduce a resolution calculus as a concise, declarative, and language- independent specification of name resolution. We develop a resolution algorithm that is sound and complete with respect to the calculus. Based on the resolution calculus we …

Patterns And Processes Of Salt Efflorescences In The Mcmurdo Region, Antarctica, Kelsey M. Bisson, Kathleen A. Welch, Susan A. Welch, Julia Meyer Sheets, W. Berry Lyons, Joseph S. Levy, Andrew G. Fountain

Geology Faculty Publications and Presentations

Evaporite salts are abundant around the McMurdo region, Antarctica (~78°S) due to very low precipitation, low relative humidity, and limited overland flow. Hygroscopic salts in the McMurdo Dry Valleys (MDVs) are preferentially formed in locations where liquid water is present in the austral summer, including along ephemeral streams, ice-covered lake boundaries, or shallow groundwater tracks. In this study, we collected salts from the Miers, Garwood, and Taylor Valleys on the Antarctic continent, as well as around McMurdo Station on Ross Island in close proximity to water sources with the goal of understanding salt geochemistry in relationship to the hydrology of …

Force Chains As The Link Between Particle And Bulk Friction Angles In Granular Material, Adam M. Booth, Ryan Hurley, Michael P. Lamb, José E. Andrade

Geology Faculty Publications and Presentations

From sediment transport in rivers to landslides, predictions of granular motion rely on a Mohr-Coulomb failure criterion parameterized by a friction angle. Measured friction angles are generally large for single grains, smaller for large numbers of grains, and no theory exists for intermediate numbers of grains. We propose that a continuum of friction angles exists between single-grain and bulk friction angles due to grain-to-grain force chains. Physical experiments, probabilistic modeling, and discrete element modeling demonstrate that friction angles decrease by up to 15° as the number of potentially mobile grains increases from 1 to ~20. Decreased stability occurs as longer …

Optimizing Data Movement In Hybrid Analytic Systems, Patrick Michael Leyshock

Dissertations and Theses

Hybrid systems for analyzing big data integrate an analytic tool and a dedicated data-management platform, storing data and operating on the data at both components. While hybrid systems have benefits over alternative architectures, in order to be effective, data movement between the two hybrid components must be minimized. Extant hybrid systems either fail to address performance problems stemming from inter-component data movement, or else require the user to explicitly reason about and manage data movement. My work presents the design, implementation, and evaluation of a hybrid analytic system for array-structured data that automatically minimizes data movement between the hybrid components. …

Synthesis Of Irreversible Incompletely Specified Multi-Output Functions To Reversible Eosops Circuits With Pse Gates, Robert Adrian Fiszer

Dissertations and Theses

As quantum computers edge closer to viability, it becomes necessary to create logic synthesis and minimization algorithms that take into account the particular aspects of quantum computers that differentiate them from classical computers. Since quantum computers can be functionally described as reversible computers with superposition and entanglement, both advances in reversible synthesis and increased utilization of superposition and entanglement in quantum algorithms will increase the power of quantum computing.

One necessary component of any practical quantum computer is the computation of irreversible functions. However, very little work has been done on algorithms that synthesize and minimize irreversible functions into a …

The Nax Language: Unifying Functional Programming And Logical Reasoning In A Language Based On Mendler-Style Recursion Schemes And Term-Indexed Types, Ki Yung Ahn

Dissertations and Theses

Two major applications of lambda calculi in computer science are functional programming languages and mechanized reasoning systems (or, proof assistants). According to the Curry--Howard correspondence, it is possible, in principle, to design a unified language based on a typed lambda calculus for both logical reasoning and programming. However, the different requirements of programming languages and reasoning systems make it difficult to design such a unified language that provides both. Programming languages usually extend lambda calculi with programming-friendly features (e.g., recursive datatypes, general recursion) for supporting the flexibility to model various computations, while sacrificing logical consistency. Logical reasoning systems usually extend …

The Geology And Petrology Of Enigmatic Rhyolites At Graveyard And Gordon Buttes, Mount Hood Quadrangle, Oregon, Elizabeth G. Westby

Dissertations and Theses

Rhyolite lava flows are found at two dome complexes at Graveyard Butte and Gordon Butte, Mount Hood Quadrangle, Oregon. At Graveyard Butte, the White River has cut a winding canyon 150 m deep, exposing at its base, a 40-meter-thick outcrop of flow-banded rhyolite (73 wt.% SiO₂, 3.67±0.01 Ma) that laterally extends along the canyon wall for about 1 km. Stratigraphically above the flow-banded rhyolite is locally-erupted iron-rich andesites (lava flows, agglutinate and other pyroclastic rocks as well as clastic debris), a rhyolitic ash-flow tuff (74 wt.% SiO₂), and the 2.77±0.36 Ma tholeiitic basalt lava flows of …