Digital Commons Network^™

Science Plan For Regional Arctic System Modeling, Andrew Roberts

Publications

Data and PDFs for "A Science Plan for Regional Arctic System Modeling" by Roberts, A. and Coauthors, 2010, IARC Technical Report 10-0001. The data collection includes the full report, a NetCDF file containing information used to illustrate and define the Arctic System in Figure 2, and supplemental PDFs of individual figures produced especially for the report. A URL is also provided that links to workshops where outcomes contributed substantially to this report. The purpose of the science plan is to provide a roadmap for understanding variability, complexity and change in the Arctic and it's adjacent environments, including understanding interconnectivity of …

Developing Proactive Methods For General Aviation Data Collection, Scott Shappell, Carla Hackworth, Kali Holcomb, John Lanicci, Massoud Bazargan, Jaclyn Baron, Rebecca Iden, Daniel Halperin

Publications

Introduction. Over the last 20 years, nearly 40,000 general aviation (GA) aircraft were involved in accidents, roughly 20% of which were fatal. To address this safety concern, scientists have often relied on accident data. Because of the rare nature of accidents, commercial aviation incident and near miss data may prove to be useful sources of safety information. In one such study, the National Transportation Safety Board interviewed GA pilots that were flying near a weather-related accident in pursuit of a different perspective than that of the accident pilot. Interviewing GA pilots about their own weather-related event may provide similar …

Model-Based Control To Enhance A Novel Two Dimensional Positioning System, Chan Yet Wong, Carlos Montes, Laine Mears, John Ziegert

Publications

This paper presents a model-based control algorithm to address the delayed feedback that occurs in a novel two dimensional positioning system. The delayed feedback causes the motion control system unable to track the desire setpoint accurately and at the same time introduce following error. Thus, a Modified Smith Predictor is proposed to address the delayed feedback by having an inner plant model to predict the path during the delay. Furthermore, an online system identification scheme is proposed to improve the accuracy of the model used in Modified Smith Predictor. Simulation and experimental results of the Modified Smith Predictor and online …

Defining An Abrasion Index For Lunar Surface Systems As A Function Of Dust Interaction Modes And Variable Concentration Zones, Ryan L. Kobrick, David M. Klaus, Kenneth W. Street Jr.

Publications

Unexpected issues were encountered during the Apollo era of lunar exploration due to detrimental abrasion of materials upon exposure to the fine-grained, irregular shaped dust on the surface of the Moon. For critical design features involving contact with the lunar surface and for astronaut safety concerns, operational concepts and dust tolerance must be considered in the early phases of mission planning. To systematically define material selection criteria, dust interaction can be characterized by two-body or three-body abrasion testing, and sub-categorically by physical interactions of compression, rolling, sliding and bending representing specific applications within the system. Two-body abrasion occurs when a …

Down Kerouac's Road To Pixar's Up, Walter C. Metz

Publications

This essay seeks to understand the startling image of Carl Fredricksen launching his house into the air using children’s helium balloons in Pixar’s animated feature, Up (2009). The film interrogates successful adulthood via the figure of the road, both in its literary manifestation in Jack Kerouac’s On the Road (1957) and cinematically, via The Wizard of Oz (Victor Fleming, 1939). Paradise Falls itself, like Oz before it, is a letdown just like the “sad paradise” of On the Road. Carl loses faith not only in his boyhood movie hero, the travelogue adventurer Charles Muntz (Christopher Plummer), but the cinema itself.

Numerical Simulation Of Marina Storage Fires Using Measured Composite Fire And Thermal Properties, Lulu Sun, Aixi Zhou, Andrew Valente

Publications

Fire test data of boats in rack storage are needed to establish more specific requirements for fire control and protection for this type of vessel in high piled rack storage configurations. Since there is no current large or full scale fire test data available, we have embarked upon testing fire and thermal properties of boat material, fiber reinforced polymer (FRP) composite, by using Differential Scanning Calorimetry, and Cone Calorimeter in order to determine the most effective method to provide sprinkler protection to an indoor boat storage facility. Fire and thermal properties of FRP were obtained from experiments and incorporated into …

Challenges To Informed Peer Review Matching Algorithms, Matthew Verleger, Heidi Diefes-Dux, Matthew W. Ohland, Mary Besterfield-Sacre, Sean Brophy

Publications

Background Peer review is a beneficial pedagogical tool. Despite the abundance of data instructors often have about their students, most peer review matching is by simple random assignment. In fall 2008, a study was conducted to investigate the impact of an informed algorithmic assignment method, called Un‐weighted Overall Need (UON), in a course involving Model‐Eliciting Activities (MEAs). The algorithm showed no statistically significant impact on the MEA Final Response scores. A study was then conducted to examine the assumptions underlying the algorithm.

Purpose (Hypothesis) This research addressed the question: To what extent do the assumptions used in making informed peer …

Deformation Waves In Microstructured Materials: Theory And Numerics, Juri Engelbrecht, Arkadi Berezovski, Mihhail Berezovski

Publications

A linear model of the microstructured continuum based on Mindlin theory is adopted which can be represented in the framework of the internal variable theory. Fully coupled systems of equations for macro-motion and microstructure evolution are represented in the form of conservation laws. A modification of wave propagation algorithm is used for numerical calculations. Results of direct numerical simulations of wave propagation in periodic medium are compared with similar results for the continuous media with the modelled microstructure. It is shown that the proper choice of material constants should be made to match the results obtained by both approaches

A Citizens Guide To National Defense And National Security, 2010 September, Clinton H. Whitehurst Jr.

Publications

A Strom Thurmond Institute Special Project

The Economic Situation, 2010 September, Bruce Yandle

Publications

Quarterly report on the economic situation of the United States and South Carolina.

2-D Absolute Positioning System For Real-Time Control Applicants, Carlos A. Montes, John C. Ziegert, Chan Wong, Laine Mears

Publications

No abstract provided.

Monster In The Dark: The Ultraluminous Grb 080607 And Its Dusty Environment, Dieter H. Hartmann, D. A. Perley, A. N. Morgan, A. Updike, F. Yuan, C. W. Awkerlof, A. A. Miller, J. S. Bloom, S. B. Cenko, W. Li

Publications

We present early-time optical through infrared photometry of the bright gamma-ray burst GRB 080607, starting only 6 s following the initial trigger in the rest frame. Complemented by our previously published spectroscopy, this high-quality photometric dataset allows us to solve for the extinction properties of the redshift 3.036 sightline, giving perhaps the most detailed information on the ultraviolet continuum absorption properties of any sightline outside our Local Group to date. The extinction properties are not adequately modeled by any ordinary extinction template (including the average Milky Way, Large Magellanic Cloud, and Small Magellanic Cloud curves), partially because the 2175 A …

Dynamic Solidification In Nanoconfined Water Films, Peter M. Hoffmann, Shah H. Khan, George Matei, Shivprasad Patil

Publications

Mechanical properties of nanoconfined water layers are still poorly understood and continue to create controversy, despite their importance for biology and nanotechnology. We report on dynamic nanomechanical measurements of water films compressed to a few single molecular layers. We show that the mechanical properties of nanoconfined water layers change significantly with their dynamic state. In particular, we observed a sharp transition from viscous to elastic response even at extremely slow compression rates, indicating that mechanical relaxation times increase dramatically once water is compressed to less than 3–4 molecular layers.

Analytic Treatment Of Vortex States In Cylindrical Superconductors In Applied Axial Magnetic Field, Andrei Ludu, J. Van Deun, M. V, Milosevic, A. Cuyt, F. M. Peeters

Publications

We solve the linear Ginzburg–Landau GL equation in the presence of a uniform magnetic field with cylindrical symmetry and we find analytic expressions for the eigenfunctions in terms of the confluent hypergeometric functions. The discrete spectrum results from an implicit equation associated to the boundary conditions and it is resolved in analytic form using the continued fractions formalism. We study the dependence of the spectrum and the eigenfunctions on the sample size and the surface conditions for solid and hollow cylindrical superconductors. Finally, the solutions of the nonlinear GL formalism are constructed as expansions in the linear GL eigenfunction basis …

Managing Alaska Soils, Thomas R. Jahns

Publications

This publication is for the gardener who wants to gain a more thorough understanding of soil basics, including soil components, texture, structure, water permeability and chemistry. There is also information on soil fertility and plant nutrients.

Oil And Gas Impacts In The Big Cypress Ecosystem: An Analysis Of Impacts Associated With Proposed Activities In The Nobles Grade Area, William Conner, Stephen E. Davis Iii, Kirsten N. Hines, John J. Cox, Dale E. Gawlik, Jerome A. Jackson, James O. Jones, Fernando Miralles-Wilhelm, Jennifer H. Richards

Publications

No abstract provided.

Three-Body Abrasion Testing Using Lunar Dust Simulants To Evaluate Surface System Materials, Ryan L. Kobrick, Kenneth G. Budinski, Kenneth W. Street Jr., David M. Klaus

Publications

Numerous unexpected operational issues relating to the abrasive nature of lunar dust, such as scratched visors and spacesuit pressure seal leaks, were encountered during the Apollo missions. To avoid reoccurrence of these unexpected detrimental equipment problems on future missions to the Moon, a series of two- and three-body abrasion tests were developed and conducted in order to begin rigorously characterizing the effect of lunar dust abrasiveness on candidate surface system materials. Two-body scratch tests were initially performed to examine fundamental interactions of a single particle on a flat surface. These simple and robust tests were used to establish standardized measurement …

Large Inverse Magnetic Entropy Changes And Magnetoresistance In The Vicinity Of A Field-Induced Martensitic Transformation In Ni50−Xcoxmn32−Yfeyga18, Arjun K. Pathak, Igor Dubenko, Haluk E. Karaca, Shane Stadler, Naushad Ali

Publications

Significantly large inverse magnetic entropy changes (ΔS_M) and magnetoresistance (MR) were observed at the inverse martensitic phase transitions of the Ga-based magnetic shape memory Heusler alloys: Ni_50−xCo_xMn_32−yFe_yGa₁₈. The crystal structures of alloys were tetragonal at 300 K and the phase transition temperatures and magnetic properties were found to be correlated with the degree of tetragonal distortion. The maximum peak values of the ΔS_M and MR at H = 5 T were determined as ≈ (+)31 J Kg⁻¹ K⁻¹ and ≈−21%, respectively, for x = 8 …

Elements Of Study On Dynamic Materials, Marine Rousseau, Gerard A. Maugin, Mihhail Berezovski

Publications

As a preliminary study to more complex situations of interest in small-scale technology, this paper envisages the elementary propagation properties of elastic waves in one-spatial dimension when some of the properties (mass density, elasticity) may vary suddenly in space or in time, the second case being of course more original. Combination of the two may be of even greater interest. Toward this goal, a critical examination of what happens to solutions at the crossing of pure space-like and time-like material discontinuities is given together with simple solutions for smooth transitions and numerical simulations in the discontinuous case. The effects on …

The Customer Isn't Always Right: Limitations Of 'Customer Service' Approaches To Education Or Why Higher Ed Is Not Burger King, Daniel E. Wueste, Teddi Fishman

Publications

The increasingly popular trend of conceptualising education in terms of 'customer service' is, in some ways, attractive. It encourages educators to think in terms of meeting students' needs and to develop innovative ways to deliver their "product." In other ways, however, it fails to convey the essential collaborative, participatory, reciprocal relationship that is central to effective teaching and learning. With respect to academic integrity, the customer service model also obscures students' roles and responsibilities. In this paper, we identify some of the ways this model provides an inappropriate metaphor for understanding the project of teaching and learning (i.e., education) and …

Scan Loss Pattern Synthesis For Adaptive Array Ground Stations, William C. Barott, Mary Ann Ingram, Paul G. Steffes

Publications

We present several techniques for maximizing the contact time between low Earth orbiting satellites (LEOs) and a ground station (GS). The GS comprises an adaptive array of electronically steered space-fed lenses (SFLs). Each SFL is manufactured as a low-cost printed circuit with the result that it exhibits scanning loss. By differently orienting the boresights of the SFLs in the adaptive array, the SFL's scanning losses can be made to optimally complement the path loss of the LEO, thereby reducing the cost of the GS while maximizing the download capacity of the satellite link. The optimization, implemented with a genetic algorithm …

Numerical Studies Of Particle Laden Flow In Dispersed Phase, Shahrdad Sajjadi, Rumma Dutta

Publications

To better understand the hydrodynamic flow behavior in turbulence, Particle-Fluid flow have been studied using our Direct Numerical(DNS) based software DSM on MUSCL-QUICK and finite volume algorithm. The particle flow was studied using Eulerian-Eulerian Quasi Brownian Motion(QBM) based approach. The dynamics is shown for various particle sizes which are very relevant to spray mechanism for Industrial applications and Bio medical applications.

On The Ph-Optimum Of Activity And Stability Of Proteins, Kemper Tally, Emil Alexov

Publications

Biological macromolecules evolved to perform their function in specific cellular environment (subcellular compartments or tissues); therefore, they should be adapted to the biophysical characteristics of the corresponding environment, one of them being the characteristic pH. Many macromolecular properties are pH dependent, such as activity and stability. However, only activity is biologically important, while stability may not be crucial for the corresponding reaction. Here, we show that the pH-optimum of activity (the pH of maximal activity) is correlated with the pH-optimum of stability (the pH of maximal stability) on a set of 310 proteins with available experimental data. We speculate that …

A Design-Build-Test-Fly Project Involving Modeling, Manufacturing, And Testing, Scott Post, Shankar Seetharaman, Sree Abimannan

Publications

This paper describes a junior-level semester-long class project for students in Fluid Mechanics courses. The goals of the project are to introduce students to engineering design, project management, and to incorporate material from other courses in engineering graphics, numerical methods, instrumentation and measurements, and manufacturing processes in a single project. The project focuses on airfoil design using computational tools, and the main emphasis lies on verification of results obtained from computational methods with experimentally measured values. Students will use the airfoil shape they select to make wings to go on a model foam glider. The final part of the project …

Effect Of Simulated Visual Impairment On Nighttime Driving Performance, Joanne Wood, Alex Chaparro, Trent Carberry, Byoung Sun Chu

Publications

Purpose. This study investigated the effects of simulated visual impairment on nighttime driving performance and pedestrian recognition under real-road conditions.

Methods. Closed road nighttime driving performance was measured for 20 young visually normal participants (M = 27.5 +- 6.1 years) under three visual conditions: normal vision, simulated cataracts, and refractive blur that were incorporated in modified goggles. The visual acuity levels for the cataract and blur conditions were matched for each participant. Driving measures included sign recognition, avoidance of low contrast road hazards, time to complete the course, and lane keeping. Pedestrian recognition was measured for pedestrians wearing either black …

Standardization Of A Volumetric Displacement Measurement For Two-Body Abrasion Scratch Test Data Analysis, Ryan L. Kobrick, David M. Klaus, Kenneth W. Street Jr.

Publications

A limitation has been identified in the existing test standards used for making controlled, two-body abrasion scratch measurements based solely on the width of the resultant score on the surface of the material. A new, more robust method is proposed for analyzing a surface scratch that takes into account the full three-dimensional profile of the displaced material. To accomplish this, a set of four volume displacement metrics are systematically defined by normalizing the overall surface profile to statistically denote the area of relevance, termed the “Zone of Interaction” (ZOI). From this baseline, depth of the trough and height of the …

Reforming Or Rejecting The Reference Desk: Conflict And Continuity In The Concept Of Reference, David S. Nolen

Publications

This paper contends that the schism between pro- and anti-reference desk librarians is not a true dichotomy. By examining the published literature on the topic, this paper asserts that the two sides actually agree that human-mediation is fundamental to references services, although the articles do examine varying methods for the delivery of reference services. While some emphasize the need to incorporate a more computer-mediated model of reference, most do not truly reject human-mediation as necessary. Those that do fail to provide a satisfactory alternative in the current social and technological context.

Uaa Student Showcase Journal: Recognizing Excellence (2010), N/A N/A

Publications

No abstract provided.

A Non-Autonomous Second Order Boundary Value Problem On The Half-Line, Gregory S. Spradlin

Publications

By variational arguments, the existence of a solution to a nonautonomous second-order boundary problem on the half-line is proven. The corresponding autonomous problem has no solution, revealing significant differences between the autonomous and the non-autonomous case.

Game Changers, Eric C. Shoaf

Publications

An introduction to the issue is presented in which the editor discusses the concept of game changer and its relation to libraries and information technology and examines the influence of emerging methods of data preservation, the Kindle book reader from online book retailer Amazon.com, and the effects of online access to information and education.