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    Integrative Remote Sensing Applications to Understanding Noctilucent Clouds and the Greenland Ice Sheet

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    Integrative remote sensing methods are effective in the study of large heterogeneous phenomena that contribute towards our understanding of global climatological trends. This study focuses upon two climatological subjects of integrative remote sensing techniques: glaciers and noctilucent clouds. Glaciers are considered among the most sensitive observable effects of climate change, whereas noctilucent clouds provide a means to observe the trends of a changing atmospheric composition. Through synchronized aircraft and spacecraft observations, this study verified for the first time that synchronous imagery of noctilucent cloud structures from airborne and spaceborne platforms could be obtained as similar band structures were identified, along with orthogonal structures only perceptible by the aircraft imagers. This helped to validate the processing algorithm at the day-to-night solar terminator of the Cloud Imagery and Particle Size (CIPS) instrument on the NASA Aeronomy of Ice in the Mesosphere (AIM) satellite. Furthermore, integrative methods were successful in determining the sliding component of glacial motion along the flowlines leading to the Sermeq Avannarleq glacier in Greenland and correlating this component to bedrock topography. Using a combination of airborne, spaceborne, and in-situ measurements, it was found that the initial onset of sliding occurs near the equilibrium line, quickly constituting approximately half of overall motion and increase steadily to the terminus, providing insight to positive feedback mechanisms that could accelerate glacial disintegration

    Integrative Remote Sensing Applications to Understanding Noctilucent Clouds and the Greenland Ice Sheet

    Get PDF
    Integrative remote sensing methods are effective in the study of large heterogeneous phenomena that contribute towards our understanding of global climatological trends. This study focuses upon two climatological subjects of integrative remote sensing techniques: glaciers and noctilucent clouds. Glaciers are considered among the most sensitive observable effects of climate change, whereas noctilucent clouds provide a means to observe the trends of a changing atmospheric composition. Through synchronized aircraft and spacecraft observations, this study verified for the first time that synchronous imagery of noctilucent cloud structures from airborne and spaceborne platforms could be obtained as similar band structures were identified, along with orthogonal structures only perceptible by the aircraft imagers. This helped to validate the processing algorithm at the day-to-night solar terminator of the Cloud Imagery and Particle Size (CIPS) instrument on the NASA Aeronomy of Ice in the Mesosphere (AIM) satellite. Furthermore, integrative methods were successful in determining the sliding component of glacial motion along the flowlines leading to the Sermeq Avannarleq glacier in Greenland and correlating this component to bedrock topography. Using a combination of airborne, spaceborne, and in-situ measurements, it was found that the initial onset of sliding occurs near the equilibrium line, quickly constituting approximately half of overall motion and increase steadily to the terminus, providing insight to positive feedback mechanisms that could accelerate glacial disintegration

    The Design and Integration of an Airborne Imager and Flight Campaign to Study the Time Evolution and Vertical Structures of Polar Mesospheric Clouds

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    The scientific objective of this study is to design an aircraft flight experiment that will provide airborne imaging data, augmenting satellite data, to advance the fundamental understanding of polar mesospheric clouds (PMCs). By capturing simultaneous top and bottom views of the PMCs, these airborne images will both provide insight into the time evolution of PMCs, and into the micro-features of these clouds, from which gravity waves and other details of the clouds vertical structures may be obtained. These data may help us better understand the driving mechanisms of these clouds and ultimately those elements of global climatic change, which are believed to cause their expanding presence. The proposed imager will use a similar charged-coupled device and interface as that of the Aeronomy of Ice in the Mesosphere’s (AIM’s) Cloud Imager and Particle Size (CIPS) imager and will observe the clouds in both the visible spectra and in a near-ultraviolet spectrum closer to the sensitivity of the CIPS imager. The sensor is to be integrated aboard UTSIs Piper Navajo. Algorithms for satellite intercept trajectories and airborne imager positioning are developed for flight campaigns, scheduled for the 2007 Boreal Summer along a series of airstrips in both Northern Quebec and Alaska

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis

    Dispelling the Myths Behind First-author Citation Counts

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    We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more sophisticated methods

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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