Physical Sciences and Mathematics Commons^™

Lettau Affect Colloquium: Or Seeing Natural Philosophy With Len, L. F. Hall

Leonard F. Hall

I was a Senior-Grad student in the Department of Meteorology at the University of Wisconsin at Madison on 19 December 1969. After purchasing a camera to photograph motorcycle trips, I returned to the 13th floor of the Meteorology and Space Science building in time to attend the annual slide show presented by Professor Heinz H. Lettau. Slides were collected from department members to augment his own and Dr. Lettau organized and presented the set. It was a feast of previously unnoticed phenomena that enriched my life. This presentation of photos and composites celebrates a rich contribution of a Doktor Vater …

Galaxies: Island Universes In The Cosmos, Shane L. Larson

Colloquia and Seminars

No abstract provided.

Probing The Milky Way With Lisa: Extracting Astrophysics From The Compact Binary Population, Shane L. Larson

Colloquia and Seminars

No abstract provided.

Airglow Observations And Modeling Of F Region Depletion Zonal Velocities Over Christmas Island, N. P. Chapagain, Michael J. Taylor, K. Nielsen, M. J. Jarvis

All Physics Faculty Publications

We report image measurements of plasma depletions in the equatorial F region ionosphere over Christmas Island (2.1°N, 157.4°W; dip latitude 2.8°N) in the central Pacific Ocean. The observations were made during the equinox period, September‐October 1995, using a Utah State University CCD imaging system filtered to observe thermospheric O I (630.0 nm) airglow emissions centered at ∼280 km altitude. Well‐defined magnetic field‐aligned depletions were observed on 18 nights during the campaign, including strong postmidnight fossilized structures, enabling detailed measurements of their morphology and dynamics. The number of depletions was influenced by their initial onset times and their persistence. The separations …

Numerical Evaluation Of Subsurface Soil Water Evaporation Derived From Sensible Heat Balance, Masaru Sakai, Scott B. Jones, Markus Tuller

Plants, Soils, and Climate Faculty Publications

A recently introduced measurement approach allows in situ determination of subsurface soil water evaporation by means of heat-pulse probes (HPP). The latent heat component of subsurface evaporation is estimated from the residual of the sensible heat balance. This heat balance method requires measurement of vertical soil temperature and estimates of thermal properties for soil water evaporation determination. Our objective was to employ numerically simulated thermal and hydraulic processes using constant or diurnally cycled surface boundary conditions to evaluate and understand this technique. Three observation grid spacings, namely, 6 mm (tri-needle HPP), 3 mm (penta-needle HPP) and 1 mm, along with …

B ̈Acklund Transformations For Darboux Integrable Equations, Ian M. Anderson

Mathematics and Statistics Faculty Presentations

Lie symmetry reduction is typically viewed as an integration method for differential systems of finite type, that is, systems of ordinary differential equations.

In this talk I shall present two new, recent applications of Lie symmetry reduction to the study of partial differential equations.

The first gives a remarkably simple method for constructing B ̈acklund transformations.

The second also gives a simple, very general method for constructing Darboux integrable equations.

The combination of these result in a new method for constructing B ̈acklund transformations for Darboux integrable equations.

The utility of this group theoretic approach will be illustrated by a …

The Dark Side Of The Universe: Dark Matter In The Galaxy And Cosmos, Shane L. Larson

Public Talks

No abstract provided.

Seasonal Variability And Dynamics Of Mesospheric Gravity Waves Over The Andes, Neal R. Criddle, M. J. Taylor, P.-D. Pautet, Y. Zhao

Neal R Criddle

The ALO is a new facility developed for atmospheric research, located at the foot of the Andes mountain range in Cerro Pachon, Chile (30.2°S, 70.7°W). As part of a collaborative program, Utah State has a Mesospheric Temperature Mapper (MTM) on site, which is used to study short period gravity wave dynamics and temperature variations in the mesosphere-lower thermosphere region. The MTM began taking measurements of the OH(6,2) and O2(0,1) spectral bands in August 2009 and a complete profile of seasonal variation in gravity wave characteristics has been created for August 2009 through August 2010 using the OH(6,2) Band. The primary …

On The Use Of Log-Transformation Vs. Nonlinear Regression For Analyzing Biological Power-Laws, Xiao Xiao

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Power-law relationships are among the most well-studied functional relationships in biology . Recently the common practice of fitting power-laws using linear regression on log-transformed data (LR) has been criticized, calling into question the conclusions of hundreds of studies. It has been suggested that nonlinear regression (NLR) is preferable, but no rigorous comparison of these two methods has been conducted. Using Monte Carlo simulations we demonstrate that the error distribution determines which method performs better, with LR better characterizing data with multiplicative lognormal error and NLR better characterizing data with additive normal error. Analysis of 471 biological power-laws shows that both …

An Ethnographic Study Of In-Service And Pre-Service Teacher Collaboration In The Development And Execution Of Mathematics Lessons, Jessica Munns

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

While much is known about effective strategies for teaching mathematics, less is understood about how to lead new teachers to employ research-based practices in their work. To address this issue we followed a Methods of Teaching Secondary and Middle School Mathematics course at Utah State University where collaboration between inservice and pre-service teachers was emphasized. This report documents examples of the implementation of research-based teaching practices by collaborative groups during the course. The structure of collaboration followed a lesson study model involving research and planning, execution and observation, and reflection and revision of lessons. Preservice and in-service teachers met twice …

Large Shift In Source Of Fine Sediment In The Upper Mississippi River, Patrick Belmont, Karen B. Gran, Shawn P. Schottler, Peter Wilcock, Stephanie S. Day, Carrie Jennings, J. Wesley Lauer, Enrica Viparelli, Jane K. Willenbring, Daniel R. Engstrom, Gary Parker

Watershed Sciences Faculty Publications

Although sediment is a natural constituent of rivers, excess loading to rivers and streams is a leading cause of impairment and biodiversity loss. Remedial actions require identification of the sources and mechanisms of sediment supply. This task is complicated by the scale and complexity of large watersheds as well as changes in climate and land use that alter the drivers of sediment supply. Previous studies in Lake Pepin, a natural lake on the Mississippi River, indicate that sediment supply to the lake has increased 10-fold over the past 150 years.Herein we combine geochemical fingerprinting and a suite of geomorphic change …

Revisiting Scaling Laws In River Basins: New Considerations Across Hillslope And Fluvial Regimes, Chandana Gangodagamage, Patrick Belmont, Efi Foufoula-Georgiou

Watershed Sciences Faculty Publications

Increasing availability of high‐resolution (1 m) topography data and enhanced computational processing power present new opportunities to study landscape organization at a detail not possible before. Here we propose the use of “directed distance from the divide” as the scale parameter (instead of Horton’s stream order or upstream contributing area) for performing detailed probabilistic analysis of landscapes over a broad range of scales. This scale parameter offers several advantages for applications in hydrology, geomorphology, and ecology in that it can be directly related to length‐scale dependent processes, it can be applied seamlessly across the hillslope and fluvial regimes, and it …

Lakes As Buffers Of Stream Dissolved Organic Matter (Dom) Variability: Temporal Patterns Of Dom Characteristics In Mountain Stream-Lake Systems, K. J. Goodman, Michelle A. Baker, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

Lakes within fluvial networks may affect dissolved organic matter (DOM) dynamics in streams by dampening spring DOM snowmelt flushing responses and/or by increasing summer DOM production. We assessed the temporal variability of dissolved organic carbon (DOC) concentration and DOM characteristics (specific ultraviolet absorbance (SUVA254); DOC:dissolved organic nitrogen (DOC:DON)), as well as DOC export in seven paired lake inflows and outflows in the Sawtooth Mountain lake district, Idaho. We hypothesized that lakes would decrease stream DOM temporal variability and increase DOM export as a result of autotrophic production. We correlated DOM variability with landscape factors to evaluate potential drivers of DOM …

Closing The Gap Between Watershed Modeling, Sediment Budgeting, And Stream Restoration, Sean M.C. Smith, Patrick Belmont, Peter Wilcock

Watershed Sciences Faculty Publications

The connection between stream restoration and sediment budgeting runs both ways: stream restoration is proposed as a means to reduce sediment yields, but an accurate understanding of sediment supply is necessary to design an effective project. Recent advances in monitoring technology, geochemical techniques, high-resolution topography data, and numerical modeling provide new opportunities to estimate sediment erosion, transport, and deposition rates; upscale them in a geomorphically relevant fashion; and synthesize sediment dynamics at watershed scales. For practical application at large scale, watershed models used to predict yield often do not resolve lower-order channels, leaving an essential “blind spot” regarding sediment processes. …

Mercury And Selenium Bioaccumulation In The Stromatolite Community Of The Great Salt Lake, Utah, Usa, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

No abstract provided.

Space Weather Community Operations Workshop: Planning For The Next Decade, J. J. Fulgham, Jennifer L. Meehan, W. K. Tobiska

All Physics Faculty Publications

Scenario: Japan suffers a great earthquake, a major tsunami, and a catastrophic nuclear meltdown. Telecommunications landlines and cell phone towers are inoperable in northern prefectures. This means that high-frequency (HF) radio becomes the primary means of communication to some affected areas. This also means that 3-hour forecasts of HF availability must be provided by space weather service organizations not affected by the disaster (Figure 1). Questions: How accurate are the HF predictions? How reliable is the service? How available is the information?

New Space Weather Products For Hf Radio, Gps Navigation, And Aviation, Jennifer L. Meehan

All Physics Faculty Publications

No abstract provided.

Surface Geometry And Heat Flux Effects Onnucleate Pool Boiling Of Subcooled Water In Microgravity, Troy Munro, Andrew Fassman, Heng Ban, John R. Dennison

All Physics Faculty Publications

The motivation of this nucleate boiling research is to understand the effects of surface geometry and heat flux as applied to a thin wire heater. This will further the understanding of the fundamental behaviors of boiling onset, steady state heat transfer, and bubble dynamics with respect to nucleate boiling with the goal of creating efficient thermal management systems for future space applications. Using three different thin platinum wire geometries and five different power levels, subcooled water was boiled over a period of approximately 30 seconds for 15 parabolic arcs to simulate microgravity. To represent the trends in bubbles behavior across …

Space Weather And Technological Impacts, Jennifer L. Meehan, G. Fisher, W. Murtagh

All Physics Faculty Publications

No abstract provided.

Cattle Ranchers And Conservation Easements, Roslynn Brain

Environment and Society Faculty Publications

No abstract provided.

Get Away Special: Microgravity Research Team, Getaway Special Team

Education and Outreach

No abstract provided.

Observations On Braided Thin Wire Nucleate Boiling In Microgravity, Justin P. Koeln, Jeffrey C. Boulware, Heng Ban, Jr Dennison

Publications

A microgravity experiment was conducted on the Space Shuttle Endeavor (STS-108) to observe sustained nucleate boiling of water. Subcooled water was boiled with a single strand and a braid of three 0.16. mm diameter and 80. mm long Nichrome resistive wires. A CCD video camera recorded the experiment while six thermistors recorded the temperature of the fluid at various distances from the heating element. This paper reports experimental results in observations, measurements, and data analysis. Bubble explosions were found to take place shortly after the onset of boiling for both the single and braid of wires. The explosion may produce …

Development Of Optimal Bubble-Seeding Microheaters To Study Nucleate Boiling Heat Transfer In Microgravity, Ryan Martineau

Reports and Proposals

No abstract provided.

Report For 2011 Urco Funded Experiment: Development Of Optimal Bubble-Seeding Microheaters To Study Nucleate Boiling Heat Transfer In Microgravity, Ryan Martineau

Reports and Proposals

No abstract provided.

Rank 2 Distributions Of Monge Equations: Symmetries, Equivalences, Ex-Tensions, Ian M. Anderson, B. Kruglikov

Mathematics and Statistics Faculty Publications

By developing the Tanaka theory for rank 2 distributions, we completely classify classical Monge equations having maximal finite-dimensional symmetry algebras with fixed (albeit arbitrary) pair of its orders. Investigation of the corresponding Tanaka algebras leads to a new Lie-Backlund theorem. We prove that all flat Monge equations are successive integrable extensions of the Hilbert-Cartan equation. Many new examples are provided.

Lithology And Internal Structure Of The San Andreas Fault At Depth Based On Characterization Of Phase 3 Whole-Rock Core In The San Andreas Fault Observatory At Depth (Safod) Borehole, Kelly Keighley Bradbury, James P. Evans, J. S. Chester, F. M. Chester, D. L. Kirshner

Geosciences Faculty Publications

We characterize the lithology and structure of the spot core obtained in 2007 during Phase 3 drilling of the San Andreas Fault Observatory at Depth (SAFOD) in order to determine the composition, structure, and deformation processes of the fault zone at 3 km depth where creep and microseismicity occur. A total of approximately 41 m of spot core was taken from three separate sections of the borehole; the core samples consist of fractured arkosic sandstones and shale west of the SAF zone (Pacific Plate) and sheared fine-grained sedimentary rocks, ultrafine black fault-related rocks, and phyllosilicate-rich fault gouge within the fault …

Discrete Brittle To Distributed Shearing; Results From Analysis Of The Deep Portions Of The Cajon Pass Drill Hole, James P. Evans, D Forand

Geosciences Presentations

We performed systematic structural and geochemical analyses on a suite of cored rocks from the vertical Cajon Pass, California drill hole to characterize the deformation and alteration of fault-related rocks. The drill hole lies 4 km northeast of the San Andreas Fault (SAF), and observations of deformed crystalline rock in core and outcrop provide a sample of a 5-km vertical column adjacent to the steeply dipping Cleghorn fault and span the brittle to semi-brittle deformational regime at hydrothermal conditions. The rocks in the upper 500 m of the borehole are composed of sandstones and granitoid augen gneiss, with narrow fault …

The Politics And Culture Of Climate Change: Us Actors And Global Implications, Charles Waugh

English Faculty Publications

Despite the scientific consensus on global warming, many people in the USA,—both ordinary citizens and elected leaders alike—remain skeptical of the need to act, and in fact remain skeptical of the idea that humans are contributing to global warming at all. Thus, environmental justice arguments based on United States carbon emissions and the disproportionate impact of rising temperatures and rising sea levels on tropical developing nations such as Vietnam frequently fall on deaf ears. This chapter explores the political and cultural construction of this deafness, seeking a better understanding of how and why so many Americans refuse to act to …

Achieving Real Development Impact Among Pastoralists: Lessons From Ethiopia, D. Layne Coppock

Environment and Society Faculty Publications

No abstract provided.

Catch, Treat And Release With Limited Removal Red Desert Complex Wild Horse Herd Management Areas (Lost Creek, Stewart Creek, Green Mountain, Crooks Mountain, Antelope Hills), United States Department Of The Interior, Bureau Of Land Management

Environmental Assessments (WY)

This Environmental Assessment (EA) has been prepared to disclose and analyze the environmental consequences of a "Catch, Treat and Release (CTR)" of wild horses in the Red Desert Wild Horse Herd Management Area (HMA) Complex. In addition to the proposed action of a CTR gather, removal of wild horses outside identified HMAs within the project area will also be conducted. The HMAs included in this complex are Lost Creek, Stewart Creek, Green Mountain, Crooks Mountain and Antelope Hills (See Area Map, Appendix 2). The EA is a site-specific analysis of potential impacts that could result with the implementation of a …