10,584 research outputs found

    A fast MPP algorithm for Ising spin exchange simulations

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    A very efficient massively parallel processor (MPP) algorithm is described for performing one important class of Ising spin simulations. Results and physical significance of MPP calculations using the method described is discussed elsewhere. A few comments, however, are made on the problem under study and results so far are reported. Ted Einstein provided guidance in interpreting the initial results and in suggesting calculations to perform

    A Perspective on Space Programs beyond North America

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    The popular image of space programs today is dominated by the activities of NASA, even here in Canada where our own space agency has a relatively low profile. But space exploration is a global effort, and numerous national governments undertake space activities without being well known to North Americans. This talk, originally a public lecture for the Royal Astronomical Society of Canada, revisits the history of national space programs, and discusses examples of established, emerging, and new space actors from around the globe, including the motives of governments in undertaking them. It concludes with a survey of the activities of the European Space Agency as an example of a successful and comprehensive space program in today\u27s era of international and multilateral co-operation in space

    Automated Image Interpretation for Science Autonomy in Robotic Planetary Exploration

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    Advances in the capabilities of robotic planetary exploration missions have increased the wealth of scientific data they produce, presenting challenges for mission science and operations imposed by the limits of interplanetary radio communications. These data budget pressures can be relieved by increased robotic autonomy, both for onboard operations tasks and for decision- making in response to science data. This thesis presents new techniques in automated image interpretation for natural scenes of relevance to planetary science and exploration, and elaborates autonomy scenarios under which they could be used to extend the reach and performance of exploration missions on planetary surfaces. Two computer vision techniques are presented. The first is an algorithm for autonomous classification and segmentation of geological scenes, allowing a photograph of a rock outcrop to be automatically divided into regions by rock type. This important task, currently performed by specialists on Earth, is a prerequisite to decisions about instrument pointing, data triage, and event-driven operations. The approach uses a novel technique to seek distinct visual regions in outcrop photographs. It first generates a feature space by extracting multiple types of visual information from the image. Then, in a training step using labeled exemplar scenes, it applies Mahalanobis distance metric learning (in particular, Multiclass Linear Discriminant Analysis) to discover the linear transformation of the feature space which best separates the geological classes. With the learned representation applied, a vector clustering technique is then used to segment new scenes. The second technique interrogates sequences of images of the sky to extract, from the motion of clouds, the wind vector at the condensation level — a measurement not normally available for Mars. To account for the deformation of clouds and the ephemerality of their fine-scale features, a template-matching technique (normalized cross-correlation) is used to mutually register images and compute the clouds’ motion. Both techniques are tested successfully on imagery from a variety of relevant analogue environments on Earth, and on data returned from missions to the planet Mars. For both, scenarios are elaborated for their use in autonomous science data interpretation, and to thereby automate certain steps in the process of robotic exploration

    Bis phenol epichlorohydrin condensate modification of alkyd resins

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    A method is given for the modification of alkyd resin systems with Bis-Phanol Epichlorohydrin Condensates. The properties of the modified alkyd resins are evaluated using similar unmodified alkyd resins as reference. A theory of linear esterification is postulated

    ECONOMIES OF SIZE OF A COORDINATED BIOREFINERY FEEDSTOCK HARVEST SYSTEM

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    The objective of this research is to determine the cost to harvest lignocellulosic biomass, such as crop residue and perennial grasses, for use as biorefinery feedstock, and to determine the potential economies of size that might result from a coordinated structure. The estimates show that substantial size economies are possible.Research and Development/Tech Change/Emerging Technologies,

    Integrative Investment Appraisal of a Lignocellulosic Biomass-to-Ethanol Industry

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    While theoretically more efficient than starch-based ethanol production systems, conversion of lignocellulosic biomass to ethanol is not without major challenges. A multi-region, multi-period, mixed integer mathematical programming model encompassing alternative feedstocks, feedstock production, delivery, and processing is developed. The model is used to identify key cost components and potential bottlenecks, and to reveal opportunities for reducing costs and prioritizing research. The research objective was to determine for specific regions in Oklahoma the most economical source of lignocellulosic biomass, timing of harvest and storage, inventory management, biorefinery size, and biorefinery location, as well as the breakeven price of ethanol, for a gasification-fermentation process. Given base assumptions, gasification-fermentation of lignocellulosic biomass to ethanol may be more economical than fermentation of corn grain. However, relative to conventional fermentation processes, gasification-fermentation technology is in its infancy. It remains to be seen if the technology will be technically feasible on a commercial scale.biomass, biorefinery location, ethanol, integrative investment appraisal, logistics, mixed integer programming, Resource /Energy Economics and Policy,

    Engaged: Making Large Classes Feel Small Through Blended Learning Instructional Strategies That Promote Increased Student Performance

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    It is not enough to be great at sharing information in a large classroom setting. To be an effective teacher you must be able to meaningfully engage your students with their peers and with the content. And you must do this regardless of class size or content. The issues of teaching effectively in large classroom settings have presented ongoing problems with enormous implications for both student learning and faculty performance. Issues about student engagement with the content, peers, and faculty persistently are discussed with little change in practice. However, the effective infusion of technology targeted through strategies for large-class instruction and management have great potential for increasing student performance. In this work Blended Learning Instructional Strategies (BLIS) are highlighted to effectively address common issues related to teaching and student engagement in large classroom settings
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