1,015 research outputs found

    Virtual Reference Best Practices and the College Student Experience

    Get PDF
    This capstone addressed the research question: what are today’s best practices in online reference, and how can librarians at academic institutions improve the student experience in online reference transactions? It documents one librarian’s creation of best practices for a virtual reference service based on the guidelines and practices outlined by governing bodies, commercial entities, and other libraries. During the study the practices were implemented at a higher education institution and results about the effectiveness, clarity, and overall improvement of virtual reference transactions were gathered using a mixed-methods approach. The author used related research literature as a foundation for building best practices documentation and evaluation of the results. The author described the successes and difficulties in implementing the best practices and concluded: lack of student awareness of the best practices implemented impacted satisfaction results, staff benefitted from having basic competencies defined, and outlining basic skills and defining what those skills entailed provided a needed structure for online chat

    High-temperature-materials study

    Get PDF
    Chemical vapor deposition of aluminum phosphides onto single crystals of silicon and gallium arsenide for producing high temperature operating solid state electronic device

    The Model Underlying SIMSOC

    Full text link
    http://deepblue.lib.umich.edu/bitstream/2027.42/50927/1/152.pd

    Risk Analysis Associated with Loss of Toxic Gases During Orion Landing and Recovery Operations

    Get PDF
    Mission, landing and recovery operations for the Orion crew module involve reentry into the Earth's atmosphere and the deployment of three Nomex parachutes to slow the descent before landing along the west coast of the United States. Orion may have residual fuel (hydrazine, N2H4) or coolant (ammonia, NH3) on board which are both highly toxic to crew in the event of exposure. These risks were evaluated using a first principles analysis approach through fluid dynamics modeling. Plume calculations were first performed with the ANSYS Fluent computational fluid dynamics code. Data were then extracted at locations relevant to crew safety such as the snorkel fan inlet and the egress hatch. Mixing calculations were performed to quantify exposure concentrations within the crew bay before and during egress and departure. Finally, results included herein were used to inform the Orion post-landing Concept of Operations (ConOps) so that strategies could be formulated to maintain crew safety in the event of the loss of fuel or coolant

    Seeing Red: Effects of Practice Interventions on Woodwind Students’ Accuracy in Performing Articulation

    Get PDF
    Music reading is a central part of most band programs, yet research about music reading has rarely included articulation markings. The purpose of this study was to explore the effect of four experimental practice conditions to a control condition on woodwind players’ performance of slur, accent, and staccato markings. A secondary purpose was to examine the role of working memory in performing articulation. The practice conditions used visual and kinesthetic approaches: colored notation, tracing over articulation marks, and speaking syllables. University woodwind players (N = 26) practiced short etudes on 1 day, and they returned approximately 24 hours later for retention testing. Participants’ working memory was strongly related to playing articulation on the first day of practice. Woodwind players prioritized playing slurs over accents and staccatos, and there was some support for tracing with color to support accurate performance of articulation

    Robust Projections of Future Fire Probability for the Conterminous United States

    Get PDF
    Globally increasing wildfires have been attributed to anthropogenic climate change. However, providing decision makers with a clear understanding of how future planetary warming could affect fire regimes is complicated by confounding land use factors that influence wildfire and by uncertainty associated with model simulations of climate change. We use an ensemble of statistically downscaled Global Climate Models in combination with the Physical Chemistry Fire Frequency Model (PC2FM) to project changing potential fire probabilities in the conterminous United States for two scenarios representing lower (RCP 4.5) and higher (RCP 8.5) greenhouse gas emission futures. PC2FM is a physically-based and scale-independent model that predicts mean fire return intervals from both fire reactant and reaction variables, which are largely dependent on a locale\u27s climate. Our results overwhelmingly depict increasing potential fire probabilities across the conterminous US for both climate scenarios. The primary mechanism for the projected increases is rising temperatures, reflecting changes in the chemical reaction environment commensurate with enhanced photosynthetic rates and available thermal molecular energy. Existing high risk areas, such as the Cascade Range and the Coastal California Mountains, are projected to experience greater annual fire occurrence probabilities, with relative increases of 122% and 67%, respectively, under RCP 8.5 compared to increases of 63% and 38% under RCP 4.5. Regions not currently associated with frequently occurring wildfires, such as New England and the Great Lakes, are projected to experience a doubling of occurrence probabilities by 2100 under RCP 8.5. This high resolution, continental-scale modeling study of climate change impacts on potential fire probability accounts for shifting background environmental conditions across regions that will interact with topographic drivers to significantly alter future fire probabilities. The ensemble modeling approach presents a useful planning tool for mitigation and adaptation strategies in regions of increasing wildfire risk

    Environmental Controls and Life Support System (ECLSS) Design for a Multi-Mission Space Exploration Vehicle (MMSEV)

    Get PDF
    Engineers at Johnson Space Center (JSC) are developing an Environmental Control and Life Support System (ECLSS) design for the Multi-Mission Space Exploration Vehicle (MMSEV). The purpose of the MMSEV is to extend the human exploration envelope for Lunar, Near Earth Object (NEO), or Deep Space missions by using pressurized exploration vehicles. The MMSEV, formerly known as the Space Exploration Vehicle (SEV), employs ground prototype hardware for various systems and tests it in manned and unmanned configurations. Eventually, the system hardware will evolve and become part of a flight vehicle capable of supporting different design reference missions. This paper will discuss the latest MMSEV ECLSS architectures developed for a variety of design reference missions, any work contributed toward the development of the ECLSS design, lessons learned from testing prototype hardware, and the plan to advance the ECLSS toward a flight design

    Patterns and Collective Behavior in Granular Media: Theoretical Concepts

    Full text link
    Granular materials are ubiquitous in our daily lives. While they have been a subject of intensive engineering research for centuries, in the last decade granular matter attracted significant attention of physicists. Yet despite a major efforts by many groups, the theoretical description of granular systems remains largely a plethora of different, often contradicting concepts and approaches. Authors give an overview of various theoretical models emerged in the physics of granular matter, with the focus on the onset of collective behavior and pattern formation. Their aim is two-fold: to identify general principles common for granular systems and other complex non-equilibrium systems, and to elucidate important distinctions between collective behavior in granular and continuum pattern-forming systems.Comment: Submitted to Reviews of Modern Physics. Full text with figures (2Mb pdf) avaliable at http://mti.msd.anl.gov/AransonTsimringReview/aranson_tsimring.pdf Community responce is appreciated. Comments/suggestions send to [email protected]

    Prediction of photoperiodic regulators from quantitative gene circuit models

    Get PDF
    Photoperiod sensors allow physiological adaptation to the changing seasons. The external coincidence hypothesis postulates that a light-responsive regulator is modulated by a circadian rhythm. Sufficient data are available to test this quantitatively in plants, though not yet in animals. In Arabidopsis, the clock-regulated genes CONSTANS (CO) and FLAVIN, KELCH, F-BOX (FKF1) and their lightsensitive proteins are thought to form an external coincidence sensor. We use 40 timeseries of molecular data to model the integration of light and timing information by CO, its target gene FLOWERING LOCUS T (FT), and the circadian clock. Among other predictions, the models show that FKF1 activates FT. We demonstrate experimentally that this effect is independent of the known activation of CO by FKF1, thus we locate a major, novel controller of photoperiodism. External coincidence is part of a complex photoperiod sensor: modelling makes this complexity explicit and may thus contribute to crop improvement
    • …
    corecore