624 research outputs found

    Map Collection - Accession 1535

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    The Map Collection consists of various maps from around the world and contains original maps and reproductions of historical maps. This collection focuses on maps from the Southern United States and South Carolina and North Carolina in particular, but also contain maps featuring Africa, Alabama, Arkansas, Asia, Central America, Europe, Florida, Georgia, Global, Holy Land, Kentucky, Louisiana, Mississippi, North America, South America, Tennessee, United States, Virginia, and World War II as well.https://digitalcommons.winthrop.edu/manuscriptcollection_findingaids/2577/thumbnail.jp

    Change of the plane of oscillation of a Foucault pendulum from simple pictures

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    The change of the plane of oscillation of a Foucault pendulum is calculated without using equations of motion, the Gauss-Bonnet theorem, parallel transport, or assumptions that are difficult to explain.Comment: 5 pages, 4 figure

    Working With Administration: Getting and Keeping Support for Professional Development Programs

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    Outline Positioning Your Office: The Real Organization Chart Seven Competencies Required of Faculty Developers Seven Competencies Required of Administrator

    Understanding Copepod Life-history and Diversity Using a Next-generation Zooplankton Model

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    Evolution has shaped the physiology, life history, and behavior of a species to the physical conditions and to the communities of predators and prey within its range. Within a community, the number of species is determined by both physical properties such as temperature and biological properties like the magnitude and timing of primary productivity, and ecological interactions such as predation. Despite well-known correlations between diversity and properties such as temperature, the mechanisms that drive these correlations are not well-described, especially in the oceans. The investigators will conduct a model-based investigation of diversity patterns in marine ecosystems, focusing on calanoid copepods. Diversity changes on both sides of the Atlantic suggest three main hypotheses, relating copepod diversity to environmental stability, productivity, and size-based predation. To test these, the investigators will develop a novel model of copepod population dynamics. The model treats developmental stage and mass as continua, leading to a single partial differential equation for abundance as a function of stage and mass. This approach facilitates the use of algorithms from computational fluid mechanics to resolve numerical dispersion problems that characterize many copepod abundance models. This new modeling framework will be tested by building a model for the species Calanus finmarchicus and Pseudocalanus newmani to compare the results of the model with prior observations and models for two contrasting ecosystems, the Gulf of Maine and Gulf of St. Lawrence. The model formalizes trade-offs between temperature-dependent development, mass-dependent and temperature-dependent growth, and mass-dependent mortality. A series of 1-D simulations will be conducted, encompassing a range of environmental conditions. Each simulation will be initialized with many distinct species, where a species is described by a set of parameters specifying key physiological and life history parameters. These will be coupled to a nutrient-phytoplankton-microzooplankton model and integrated for many years. This procedure will produce a community of copepods adapted to conditions in each simulated environment. By studying how the modeled copepod communities respond to changes in physical conditions, productivity, and predation, mechanisms accounting for copepod diversity patterns will be tested.The project will lead to improved models for important copepod species that can be incorporated into ongoing and future ecosystem forecasts. The information on copepod biogeographic limits developed by this study could support estimates of copepod distributions under climate change. The model will be designed to work in a basin-scale model. By allowing adaption to physical and biological conditions, the emergent copepod communities should provide more realistic estimates of the impact of climate change. The project will support the professional development of one graduate student and one postdoctoral associate. It will also engage one undergraduate summer intern each year. Concepts related to this project will be communicated to the wider public on a blog at SeascapeModeling.org

    Understanding Copepod Life-History and Diversity using a Next-Generation Zooplankton Model

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    The main goal of our project is to understand the patterns of diversity and biogeography in marine copepods. To achieve this goal, we developed a unique modeling framework to simulate the trade-offs between growth, development, and fecundity in marine copepods. We developed a new approach to modeling growth and development in metazoans. We applied this approach to marine copepods, and used it to understand relationships between copepod body size and temperature, copepod biodiversity patterns, and copepod biogeography. This project also provided support for experiments to look at how copepod body size impacts the particle size spectrum. We used our model to explain why marine copepods and other organisms with strong associations between body size and temperature should be expected to deviate from the temperature-diversity relationship that emerges from classic metabolic theory. We also used a novel emergent modeling approach to explore how temperature and chlorophyll cycles influence copepod biogeography

    Fault prediction in aircraft engines using Self-Organizing Maps

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    Aircraft engines are designed to be used during several tens of years. Their maintenance is a challenging and costly task, for obvious security reasons. The goal is to ensure a proper operation of the engines, in all conditions, with a zero probability of failure, while taking into account aging. The fact that the same engine is sometimes used on several aircrafts has to be taken into account too. The maintenance can be improved if an efficient procedure for the prediction of failures is implemented. The primary source of information on the health of the engines comes from measurement during flights. Several variables such as the core speed, the oil pressure and quantity, the fan speed, etc. are measured, together with environmental variables such as the outside temperature, altitude, aircraft speed, etc. In this paper, we describe the design of a procedure aiming at visualizing successive data measured on aircraft engines. The data are multi-dimensional measurements on the engines, which are projected on a self-organizing map in order to allow us to follow the trajectories of these data over time. The trajectories consist in a succession of points on the map, each of them corresponding to the two-dimensional projection of the multi-dimensional vector of engine measurements. Analyzing the trajectories aims at visualizing any deviation from a normal behavior, making it possible to anticipate an operation failure.Comment: Communication pr\'esent\'ee au 7th International Workshop WSOM 09, St Augustine, Floride, USA, June 200

    Impacts of intraguild predation on Arctic copepod communities

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    Communities of large copepods form an essential hub of matter and energy fluxes in Arctic marine food webs. Intraguild predation on eggs and early larval stages occurs among the different species of those communities and it has been hypothesized to impact its structure and function. In order to better understand the interactions between dominant copepod species in the Arctic, we conducted laboratory experiments that quantified intraguild predation between the conspicuous and omnivorous Metridia longa and the dominant Calanus hyperboreus. We recorded individual egg ingestion rates for several conditions of temperature, egg concentration, and alternative food presence. In each of these experiments, at least some females ingested eggs but individual ingestion rates were highly variable. The global mean ingestion rate of M. longa on C. hyperboreus eggs was 5.8 eggs ind−1 d−1, or an estimated 37% of M. longa daily metabolic need. Among the different factors tested and the various individual traits considered (prosome length, condition index), only the egg concentration had a significant and positive effect on ingestion rates. We further explored the potential ecological impacts of intraguild predation in a simple 1D numerical model of C. hyperboreus eggs vertical distribution in the Amundsen Gulf. Our modeling results showed an asymmetric relationship in that M. longa has little potential impact on the recruitment of C. hyperboreus (<3% egg standing stock removed by IGP at most) whereas the eggs intercepted by the former can account for a significant portion of its metabolic requirement during winter (up to a third)

    Radio Emission from the Exoplanetary System ε Eridani

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    As part of a wider search for radio emission from nearby systems known or suspected to contain extrasolar planets, ε Eridani was observed by the Jansky Very Large Array (VLA) in the 2–4 GHz and 4–8 GHz frequency bands. In addition, as part of a separate survey of thermal emission from solar-like stars, ε Eri was observed in the 8–12 GHz and the 12–18 GHz bands of the VLA. Quasi-steady continuum radio emission from ε Eri was detected in the three high-frequency bands at levels ranging from 67 to 83 μJy. No significant variability is seen in the quasi-steady emission. The emission in the 2–4 GHz emission, however, is shown to be the result of a circularly polarized (up to 50%) radio pulse or flare of a few minutes in duration that occurred at the beginning of the observation. We consider the astrometric position of the radio source in each frequency band relative to the expected position of the K2V star and the purported planet. The quasi-steady radio emission at frequencies ≥8 GHz is consistent with a stellar origin. The quality of the 4–8 GHz astrometry provides no meaningful constraint on the origin of the emission. The location of the 2–4 GHz radio pulse is >2.5σ from the star; however, based on the ephemeris of Benedict et al., it is not consistent with the expected location of the planet either. If the radio pulse has a planetary origin, then either the planetary ephemeris is incorrect or the emission originates from another planet
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