Physical Sciences and Mathematics Commons^™

Glacier Inventories And Change In Glacier National Park, Melissa Carrie Brett

Dissertations and Theses

Glacier National Park, in northwestern Montana, is a unique and awe-inspiring national treasure that is often used by the media and public-at-large as a window into the effects of climate change. An updated inventory of glaciers and perennial snowfields (G&PS) in the Park, along with an assessment of their change over time, is essential to understanding the role that glaciers are playing in the environment of this Park. Nine inventories between 1966 and 2015 were compiled to assess area changes of G&PS. Over that 49-year period, total area changed by nearly -34 ± 11% between 1966 and 2015. Volume change, …

Interlaboratory Comparison Of Δ13c And Δd Measurements Of Atmospheric Ch4 For Combined Use Of Data Sets From Different Laboratories, Taku Umezawa, Carl Brenninkmeijer, Thomas Röckmann, Carina Van Der Veen, Stanley C. Tyler, Ryo Fujita, Shinji Morimoto, Shuji Aoki, Todd Sowers, Jochen Schmitt, Michael Bock, Jonas Beck, Hubertus Fischer, Sylvia E. Michel, Bruce H. Vaughn, John B. Miller, James W.C. White, Gordon Brailsford, Hinrich Schaefer, Peter Sperlich, Willi A. Brand, Michael Rothe, Thomas Blunier, David Lowry, Rebecca E. Fisher, Euan G. Nisbet, Andrew L. Rice, Peter Bergamaschi, Cordelia Veidt, Ingeborg Levin

Physics Faculty Publications and Presentations

We report results from a worldwide interlaboratory comparison of samples among laboratories that measure (or measured) stable carbon and hydrogen isotope ratios of atmospheric CH₄ (δ¹³C-CH₄ and δD-CH₄). The offsets among the laboratories are larger than the measurement reproducibility of individual laboratories. To disentangle plausible measurement offsets, we evaluated and critically assessed a large number of intercomparison results, some of which have been documented previously in the literature. The results indicate significant offsets of δ¹³C-CH₄ and δD- CH₄ measurements among data sets reported from different laboratories; the differences among laboratories …

A Virtual Lock-In Amplifier, Spectrum Analyzer, Impedance Meter And Semiconductor Analyzer Implemented On An Sr7265 Hardware Target, Jianghua Bai, John L. Freeouf, Andres H. La Rosa

Physics Faculty Publications and Presentations

Lock-in amplifiers are used to detect and measure very small AC signals down to the range of nVs. Accurate measurements may be made even when the small signals are buried by noise sources thousands of times larger. With the digital signal processing (DSP) technology involved in modern instrumentation, a lock-in amplifier is more versatile than sensing and recover small signals. Combining the virtual instrumentation technology, we reorganize the functional blocks of a programmable lock-in amplifier and build it as a virtual spectrum analyzer, virtual impedance meter, virtual network analyzer, virtual semiconductor parameter analyzer, signal generator, etc. A 4 layer model …

Implementing An Spm Controller With Labview, Jianghua Bai, John L. Freeouf, Andres H. La Rosa

Physics Faculty Publications and Presentations

The purpose of this article is to reduce the barrier of developing a house-made scanning probe microscope(SPM). Here in this paper,we cover all the details of programming an SPM controller with LabVIEW. The main controller has three major sequential portions. They are system initialization portion,scan control and image display portion and system shutdown portion. The most complicated and essential part of the main controller is the scan control and image display portion, which is achieved with various parallel tasks. These tasks are scan area and image size adjusting module, Y-axis scan control module, Xaxis scan and image transferring module, parameters …

Evidence-Based Causal Chains For Linking Health, Development, And Conservation Actions, Jiangxiao Qiu, Edward Game, Heather Tallis, Lydia Olander, Louise Glew, James S. Kagan, Multiple Additional Authors

Institute for Natural Resources Publications

Sustainability challenges for nature and people are complex and interconnected, such that effective solutions require approaches and a common theory of change that bridge disparate disciplines and sectors. Causal chains offer promising approaches to achieving an integrated understanding of how actions affect ecosystems, the goods and services they provide, and ultimately, human well-being. Although causal chains and their variants are common tools across disciplines, their use remains highly inconsistent, limiting their ability to support and create a shared evidence base for joint actions. In this article, we present the foundational concepts and guidance of causal chains linking disciplines and sectors …

Development And Field Validation Of An Environmental Dna (Edna) Assay For Invasive Clams Of The Genus Corbicula, Dominique A. Cowart, Mark A. Renshaw, Crysta Gantz, John Umek, Sudeep Chandra, Scott P. Egan, David M. Lodge, Eric R. Larson

Environmental Science and Management Faculty Publications and Presentations

Early detection is imperative for successful control or eradication of invasive species, but many organisms are difficult to detect at the low abundances characteristic of recently introduced populations. Environmental DNA (eDNA) has emerged as a promising invasive species surveillance tool for freshwaters, owing to its high sensitivity to detect aquatic species even when scarce. We report here a new eDNA assay for the globally invasive Asian clam Corbicula fluminea (Müller, 1774), with field validation in large lakes of western North America. We identified a candidate primer pair for the Cytochrome c oxidase subunit 1 (COI) gene for C. fluminea. We …

Drivers Of Solar Radiation Variability In The Mcmurdo Dry Valleys, Antarctica, Maciej K. Obryk, Andrew G. Fountain, Peter T. Doran

Geology Faculty Publications and Presentations

Annually averaged solar radiation in the McMurdo Dry Valleys, Antarctica has varied by over 20 W m−2 during the past three decades; however, the drivers of this variability are unknown. Because small differences in radiation are important to water availability and ecosystem functioning in polar deserts, determining the causes are important to predictions of future desert processes. We examine the potential drivers of solar variability and systematically eliminate all but stratospheric sulfur dioxide. We argue that increases in stratospheric sulfur dioxide increase stratospheric aerosol optical depth and decrease solar intensity. Because of the polar location of the McMurdo Dry Valleys …

Development Of A Liquid Contacting Method For Investigating Photovoltaic Properties Of Pbs Quantum Dot Solids, Vitalii Alekseevich Dereviankin

Dissertations and Theses

Photovoltaic (PV) devices based on PbS quantum dot (QD) solids demonstrate high photon-to-electron conversion yields. However, record power conversion efficiencies remain limited mainly due to bulk and interfacial defects in the light absorbing material (QD solids). Interfacial defects can be formed when a semiconductor, such as QD solid, is contacted by another material and may predetermine the semiconductor/metal or semiconductor/metal-oxide junction properties. The objective of the work described in this dissertation was set to explore whether electrochemical contacting using liquid electrolytes can provide sufficient means of contacting the QD solids to investigate their PV performance without introducing the unwanted interfacial …

Opportunity Identification For New Product Planning: Ontological Semantic Patent Classification, Farshad Madani

Dissertations and Theses

Intelligence tools have been developed and applied widely in many different areas in engineering, business and management. Many commercialized tools for business intelligence are available in the market. However, no practically useful tools for technology intelligence are available at this time, and very little academic research in technology intelligence methods has been conducted to date.

Patent databases are the most important data source for technology intelligence tools, but patents inherently contain unstructured data. Consequently, extracting text data from patent databases, converting that data to meaningful information and generating useful knowledge from this information become complex tasks. These tasks are currently …

Decision Support System For The Design And Planning Of Low-Impact Development Practices: The Case Of Seoul, Jae-Yeol Song, Eun-Sung Chung, Soo Hyun Kim

Civil and Environmental Engineering Faculty Publications and Presentations

This study presented the conceptual framework of the water-management analysis module (WMAM) to derive effective physical specifications for the design and planning of low-impact development (LID) practices using the storm-water management model (SWMM). This decision-support system can be used for six LID types and has the following key capabilities: determining relevant LID design parameters within the SWMM that critically influence the hydrological cycle components using a simple sensitivity analysis and determining the best hydrological values for LID planning specification. This study analyzed a highly urbanized university campus as a case study to determine the design and planning specifications for an …

A Machine Learning Algorithm For Identifying And Tracking Bacteria In Three Dimensions Using Digital Holographic Microscopy, Manuel Bedrossian, Marwan El-Kholy, Daniel Neamati, Jay Nadeau

Physics Faculty Publications and Presentations

Digital Holographic Microscopy (DHM) is an emerging technique for three-dimensional imaging of microorganisms due to its high throughput and large depth of field relative to traditional microscopy techniques. While it has shown substantial success for use with eukaryotes, it has proven challenging for bacterial imaging because of low contrast and sources of noise intrinsic to the method (e.g. laser speckle). This paper describes a custom written MATLAB routine using machine-learning algorithms to obtain three-dimensional trajectories of live, lab-grown bacteria as they move within an essentially unrestrained environment with more than 90% precision. A fully annotated version of the software used …

Benefit Relevant Indicators: Ecosystem Services Measures That Link Ecological And Social Outcomes, Lydia Olander, Robert J. Johnston, Heather Tallis, James S. Kagan, Lynn A. Maguire, Stephen Polasky, Dean Urban, James Boyd, Lisa Wainger, Margaret A. Palmer

Institute for Natural Resources Publications

There is a growing movement in government, environmental non-governmental organizations and the private sector to include ecosystem services in decision making. Adding ecosystem services into assessments implies measuring how much a change in ecological conditions affects people, social benefit, or value to society. Despite consensus around the general merit of accounting for ecosystem services, systematic guidance on what to measure and how is lacking. Current ecosystem services assessments often resort to biophysical proxies (e.g., area of wetland in a floodplain) or even disregard services that seem difficult to measure. Valuation, an important tool for assessing trade-offs and comparing outcomes, is …

The Interactive Effect Of Multiple Stressors On Crustacean Zooplankton Communities In Montane Lakes, Jeffrey Thomas Brittain, Angela L. Strecker

Environmental Science and Management Faculty Publications and Presentations

Nonnative fish introductions have altered thousands of naturally fishless montane lakes, resulting in cascading food web repercussions. Nitrogen deposition has been recognized as an anthropogenic contributor to acidification and eutrophication of freshwater ecosystems, which may affect the abundance and composition of planktonic communities. This study identified responses of zooplankton communities from two lakes (fish present versus absent) in Mount Rainier National Park to manipulations simulating an episodic disturbance of acidification and eutrophication via nitrogen addition in mesocosms. Zooplankton communities from lakes with different food web structure (i.e., fish present or absent) responded differently to the singular effects of acid and …

Flavour Chemicals In A Sample Of Non-Cigarette Tobacco Products Without Explicit Flavour Names Sold In New York City In 2015, Shannon M. Farley, Kevin R.J. Schroth, Victoria Grimshaw, Wentai Luo, Julia Lynn Degagne, Peyton A. Tierney, Kilsun Kim, James F. Pankow

Chemistry Faculty Publications and Presentations

Background Youth who experiment with tobacco often start with flavoured products. In New York City (NYC), local law restricts sales of all tobacco products with ‘characterising flavours’ except for ‘tobacco, menthol, mint and wintergreen’. Enforcement is based on packaging: explicit use of a flavour name (eg, ‘strawberry’) or image depicting a flavour (eg, a fruit) is presumptive evidence that a product is flavoured and therefore prohibited. However, a tobacco product may contain significant levels of added flavour chemicals even when the label does not explicitly use a flavour name.

Methods Sixteen tobacco products were purchased within NYC in 2015 that …

Among‐Species Overlap In Rodent Body Size Distributions Predicts Species Richness Along A Temperature Gradient, Quentin D. Read, John M. Grady, Phoebe Zarnetske, Sydne Record, Benjamin Baiser, Jonathan Belmaker, Mao-Ning Tuanmu, Angela L. Strecker, Lydia Beaudrot, Katherine M. Thibault

Environmental Science and Management Faculty Publications and Presentations

Temperature is widely regarded as a major driver of species richness, but the mechanisms are debated. Niche theory suggests temperature may affect richness by filtering traits and species in colder habitats while promoting specialization in warmer ones. However, tests of this theory are rare because niche dimensions are challenging to quantify along broad thermal gradients. Here, we use individual-level trait data from a long-term monitoring network spanning a large geographic extent to test niche-based theory of community assembly in small mammals. We examined variation in body size among 23 communities of North American rodents sampled across the National Ecological Observatory …

A Multi-Year Data Set On Aerosol-Cloud-Precipitation-Meteorology Interactions For Marine Stratocumulus Clouds, Armin Sorooshian, Alexander B. Macdonald, Hossein Dadashazar, Kelvin H. Bates, Matthew M. Coggon, Jill S. Craven, Ewan Crosbie, Scott P. Hersey, Natasha Hodas, Jack J. Lin, Arnaldo Negrón Marty, Lindsay C. Maudlin, Andrew R. Metcalf, Shane M. Murphy, Luz T. Padró, Gouri Prabhakar, Tracey A. Rissman, Taylor Shingler, Varuntida Varutbangkul, Zhen Wang, Roy K. Woods, Patrick Y. Chuang, Athanasios Nenes, Haflidi H. Jonsson, Richard C. Flagan, John H. Seinfeld

Environmental Science and Management Faculty Publications and Presentations

Airborne measurements of meteorological, aerosol, and stratocumulus cloud properties have been harmonized from six field campaigns during July-August months between 2005 and 2016 off the California coast. A consistent set of core instruments was deployed on the Center for Interdisciplinary Remotely- Piloted Aircraft Studies Twin Otter for 113 flight days, amounting to 514 flight hours. A unique aspect of the compiled data set is detailed measurements of aerosol microphysical properties (size distribution, composition, bioaerosol detection, hygroscopicity, optical), cloud water composition, and different sampling inlets to distinguish between clear air aerosol, interstitial in-cloud aerosol, and droplet residual particles in cloud. Measurements …

Statistical Analysis Of Network Change, Teresa D. Schmidt, Martin Zwick

Systems Science Faculty Publications and Presentations

Networks are rarely subjected to hypothesis tests for difference, but when they are inferred from datasets of independent observations statistical testing is feasible. To demonstrate, a healthcare provider network is tested for significant change after an intervention using Medicaid claims data. First, the network is inferred for each time period with (1) partial least squares (PLS) regression and (2) reconstructability analysis (RA). Second, network distance (i.e., change between time periods) is measured as the mean absolute difference in (1) coefficient matrices for PLS and (2) calculated probability distributions for RA. Third, the network distance is compared against a reference distribution …

When Good Components Go Bad: Formally Secure Compilation Despite Dynamic Compromise, Guglielmo Fachini, CăTăLin Hriţcu, Marco Stronati, Arthur Azevedo De Amorim, Carmine Abate, Roberto Blanco, Théo Laurent, Benjamin C. Pierce, Andrew Tolmach

Computer Science Faculty Publications and Presentations

We propose a new formal criterion for secure compilation, giving strong end-to-end security guarantees for software components written in unsafe, low-level languages with C-style undefined behavior. Our criterion is the first to model dynamic compromise in a system of mutually distrustful components running with least privilege. Each component is protected from all the others—in particular, from components that have encountered undefined behavior and become compromised. Each component receives secure compilation guarantees up to the point when it becomes compromised, after which an attacker can take complete control over the component and use any of its privileges to attack the remaining …

Sosiel: A Cognitive, Multi-Agent, And Knowledge-Based Platform For Modeling Boundedly-Rational Decision-Making, Garry Sotnik

Dissertations and Theses

Decision-related activities, such as bottom-up and top-down policy development, analysis, and planning, stand to benefit from the development and application of computer-based models that are capable of representing spatiotemporal social human behavior in local contexts. This is especially the case with our efforts to understand and search for ways to mitigate the context-specific effects of climate change, in which case such models need to include interacting social and ecological components. The development and application of such models has been significantly hindered by the challenges in designing artificial agents whose behavior is grounded in both empirical evidence and theory and in …

Social Position Influencing The Water Perception Gap Between Local Leaders And Constituents In A Socio-Hydrological System, Melissa Haeffner, Douglas Jackson-Smith, Courtney G. Flint

Environmental Science and Management Faculty Publications and Presentations

How well city leaders represent their constituents and meet their needs are key concerns in transitioning to local sustainable water governance. To date, however, there is little research documenting the influence of social position between elected leaders who make policy, career staff water managers who design and operate systems and implement policies, and the members of the public whose individual water use behaviors are important drivers of water sustainability outcomes. In this study, we ask: ‘‘How does social position explain variation in water perceptions and concerns between different actors in a sociohydrological system?’’ Using a mixed method approach with survey …

Apprehensive Drought Characteristics Over Iraq: Results Of A Multidecadal Spatiotemporal Assessment, Maysoun Ayad Hameed, Ali Ahmadalipour, Hamid Moradkhani

Civil and Environmental Engineering Faculty Publications and Presentations

Drought is an extreme climate phenomenon that happens slowly and periodically threatens the environmental and socio-economic sectors. Iraq is one of the countries in the Middle East that has been dealing with serious drought-related issues in the 21st century. Here, we investigate meteorological drought across Iraq from 1948 to 2009 at 0.25° spatial resolution. The Standardized Precipitation Evapotranspiration Index (SPEI) has been utilized as a multi-scalar drought index accounting for the effects of temperature variability on drought. Four of the main characteristics of drought including extent, intensity, frequency and duration are studied and the associated spatiotemporal patterns are investigated for …

Mechanisms And Identification Of Unsteady Separation Development And Remediation, Matthew Scott Melius

Dissertations and Theses

Unsteady flow separation represents a highly complex and important area of study within fluid mechanics. The extent of separation and specific time scales over which it occurs are not fully understood and has significant consequences in numerous industrial applications such as helicopters, jet engines, hydroelectric turbines and wind turbines. A direct consequence of unsteady separation is the erratic movement of the separation point which causes highly dynamic and unpredictable loads on an airfoil. Current computational models underestimate the aerodynamic loads due to the inaccurate prediction of the emergence and severity of unsteady flow separation especially in response to a sudden …

Strong Coupling Between Photonic Cavities, Xiang Wei

Dissertations and Theses

As the performance of computers has improved dramatically since the 1990s, many interesting photonic crystal properties have been theoretically and experimentally discovered. For example, the strong coupling between photonic crystal cavities was revealed in the 2000s; many groups have successfully fabricated these cavities and verified strong coupling experimentally using silicon. In this thesis, instead of using silicon, we present new results on photonic crystals made by thin indium tin oxide (ITO) layers. Compared to silicon, ITO is not an ideal material to make a photonic crystal because of its comparatively low refractive index and limited transparency. However, it is an …

The Wildland-Urban Interface Raster Dataset Of Catalonia, Fermín J. Alcasena, Cody Evers, Cristina Vega-Garcia

Environmental Science and Management Faculty Publications and Presentations

We provide the wildland urban interface (WUI) map of the autonomous community of Catalonia (Northeastern Spain). The map encompasses an area of some 3.21 million ha and is presented as a 150-m resolution raster dataset. Individual housing location, structure density and vegetation cover data were used to spatially assess in detail the interface, intermix and dispersed rural WUI communities with a geographical information system. Most WUI areas concentrate in the coastal belt where suburban sprawl has occurred nearby or within unmanaged forests. This geospatial information data provides an approximation of residential housing potential for loss given a wildfire, and represents …

E‑Cigarette Airflow Rate Modulates Toxicant Profiles And Can Lead To Concerning Levels Of Solvent Consumption, Tetiana Korzun, Maryana Lazurko, Tetiana Korzun, Ian Munhenzva, Kelley Barsanti, Yilin Huang, R. Paul Jensen, Jorge O. Escobedo, Wentai Luo, David H. Peyton, Robert M. Strongin

Chemistry Faculty Publications and Presentations

Electronic cigarettes enabling enhanced airflow have grown in popularity in recent years. The objective of this study is to show that flow rates modulate the levels of specific aerosol toxicants produced in electronic cigarettes. Flow rates used in various laboratory investigations involving e-cigarettes have varied widely to date, and can thus promote interlaboratory variability in aerosol product profiles. The thermal decomposition of hydroxyacetone and glycolaldehyde is less favorable at lower temperatures, supporting the observations of these products at higher flow rates/lower heating coil temperatures. Higher temperatures promote the formation of acetaldehyde from hydroxyacetone and formaldehyde from both hydroxyacetone and glycolaldehyde. …

Analysis Of Residential And Auto Break-In Records In Taipei City, Afnan Althoupety, Aishwarya Joy, Juchun Cheng, Priyanka Patil, Tejas Deshpande

Engineering and Technology Management Student Projects

Taipei City is the capital of Taiwan. It has population of 2.7 million living in the city area of 271 km2 (104 mi2). There are totally 12 administrative districts in this city. To maintain the safety of the city, Taipei City Police Bureau has arranged regular patrol routes with focus on the high-risk area where residential and auto break-in occurs. Due to limited police resource, resident neighborhood also organized volunteered patrol teams to enhance the security in residential area. Based on past file record history, the Bureau would like to understand the high-risk districts and time schedule to improve their …

Campus Sustainability Office Annual Report, 2017-2018, Campus Sustainability Office

Campus Sustainability Office Publications, Reports and Presentations

The Campus Sustainability Office 2017-2018 annual report.

Psu Green Building Internship Final Report, 2018: Karl Miller Center Post-Occupancy Study, Omar Abu Sulaiman, Jocelyn Reynolds

Campus Sustainability Office Publications, Reports and Presentations

In this report, both occupant comfort perception-based data, collected via surveys, and building performance-based data, collected via sensors, are utilized to conduct a post-occupancy evaluation of Portland State University’s (PSU) new Karl Miller Center (KMC), formerly known as the School of Business Administration. The KMC was completed in September 2017 and is on track to earn LEED Platinum certification, primarily for the passive ventilation strategies incorporated into its design. The environmental factors studied in this report are air and concrete slab temperatures, CO2 levels, and airflow. The personal factors studied in this report are clothing levels (clo), gender identity, thermal …

Stars Annual Report, 2018, Campus Sustainability Office

Campus Sustainability Office Publications, Reports and Presentations

The Campus Sustainability Office (CSO) compiles information from departments across campus annually to complete the STARS Report. The score is based on the number of points received across five categories: Academics, Engagement, Operations, and Planning & Administration, and Innovation & Leadership. PSU has maintained a Gold rating since the institution began reporting in 2011 and is within the top 40 of over 400 reporting institutions. This summary includes improvement opportunities to assist our efforts to eventually become a STARS Platinum institution. For more information on improvement opportunities please contact Amanda Wolf at wolf@pdx.edu

Utility Summary Fiscal Year 2018, Campus Sustainability Office

Campus Sustainability Office Publications, Reports and Presentations

Summary of energy use listed by building