41 research outputs found

    Pilot Information Needs for Electronic Data-Driven Charts

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    Electronic charting technology is evolving from “fixed” raster-based charts to data-driven charts, in which information elements shown on the chart can be reconfigured during flight. Specifically, we were interested in identifying a set of minimum information requirements for a concept in which pilots brief with a fixed chart showing all information elements but then fly with an electronic chart, which may or may not include all the information elements that were briefed. Two hundred twenty-nine pilots rated the importance of information elements shown on four different types of aeronautical charts. We analyzed the data using one-way chi-square tests to identify a criticality “level” for each information element. This information was then used to identify a “minimum set.” This paper presents an overview of the findings

    Pilot Information Needs for Electronic Data-Driven Charts

    Get PDF
    Electronic charting technology is evolving from “fixed” raster-based charts to data-driven charts, in which information elements shown on the chart can be reconfigured during flight. Specifically, we were interested in identifying a set of minimum information requirements for a concept in which pilots brief with a fixed chart showing all information elements but then fly with an electronic chart, which may or may not include all the information elements that were briefed. Two hundred twenty-nine pilots rated the importance of information elements shown on four different types of aeronautical charts. We analyzed the data using one-way chi-square tests to identify a criticality “level” for each information element. This information was then used to identify a “minimum set.” This paper presents an overview of the findings

    Some Properties of Distal Actions on Locally Compact Groups

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    We consider the actions of (semi)groups on a locally compact group by automorphisms. We show the equivalence of distality and pointwise distality for the actions of a certain class of groups. We also show that a compactly generated locally compact group of polynomial growth has a compact normal subgroup KK such that G/KG/K is distal and the conjugacy action of GG on KK is ergodic; moreover, if GG itself is (pointwise) distal then GG is Lie projective. We prove a decomposition theorem for contraction groups of an automorphism under certain conditions. We give a necessary and sufficient condition for distality of an automorphism in terms of its contraction group. We compare classes of (pointwise) distal groups and groups whose closed subgroups are unimodular. In particular, we study relations between distality, unimodularity and contraction subgroups.Comment: 27 pages, main results are revised and improved, some preliminary results are removed and some new results are added, some proofs are revised and some are made shorte

    Engaging Community Partners to Enrich Preschoolers Learning Experiences with Dramatic Inquiry

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    Interdisciplinary teams of adults are needed to enhance the capacity of schools to provide the most appropriate educational experiences for young children who have or are at risk for developmental delays and disabilities (Division for Early Childhood, 2014). When educators, families, and community partners connect around shared goals, we begin to reimagine instructional opportunities and create more equitable access to educational resources for children and families. We share insights from community partners who participated in a collaborative dramatic inquiry study designed to enrich preschoolers’ learning experiences and serve children and families

    All-optical packet switch at data-rate beyond 160 Gb/s

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    Two different paradigms to realize a scalable all-optical packet switch with label swapping will be presented. All the functions required for switching the packets are based on all-optical signal processing without any electronic control. This allows very low latency and potential photonic integration of the systems. We report for both techniques experimental results showing the routing operation of the 160 Gb/s packets and beyond. We will discuss and compare both techniques in term of devices and bit-rate scalability, latency, power consumption, power penalty performance and cascadability as key parameters for the realization of an all-optical packet switch. ©2009 IEEE

    Observatory's linguistic landscape: semiotic appropriation and the reinvention of space

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    Using a longitudinal ethnographic study of the linguistic landscape (LL) in Observatory's business corridor of Lower Main Road, the paper explores changes brought about by the influx of immigrant Africans, their artefacts and language practices. The paper uses the changes in the LL over time and the development of an "African Corner" within Lower Main Road, to illustrate the appropriation of space and the unpredictability, which comes along with highly mobile, technological and multicultural citizens. It is argued that changes in the LL are part of the act of claiming and appropriating space wherein space becomes summarily recontexualized and hence reinvented and "owned" by new actors. It is also argued that space ownership can be concealed through what we have called "brand anonymity" strategies in which the identity of the owner is deliberately concealed behind global brands. We conclude that space is pliable and mobile, and that, it is the people within space who carve out new social practices in their appropriated space.IBS

    Media representations of the nouveaux riches and the cultural constitution of the global middle class

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    The article offers a distinctive account of how the nouveaux riches serve as an anchor for a range of upper- middle- class ambivalences and anxieties associated with transformations of capitalism and shifting global hierarchies. Reflecting the long- term association of middle- class symbolic boundaries with notions of refinement and respectability, it examines how the discourse of civility shapes how the nouveaux riches are represented to the upper middle class, identifying a number of recurrent media frames and narrative tropes related to vulgarity, civility, and order. The author argues that these representations play a central role in the reproduction of the Western professional middle class, and in the cultural constitution of a global middle class — professional, affluent, urban, and affiliated by an aesthetic regime of civility that transcends national borders. The findings underline the significance of representations of the new super- rich as devices through which the media accomplish the global circulation of an upper- middle- class repertoire of cultural capital, which is used both to police shifting class boundaries and to establish a legitimate preserve for univorous snobbishness

    Ecological Meltdown in the Firth of Clyde, Scotland: Two Centuries of Change in a Coastal Marine Ecosystem

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    BACKGROUND: The Firth of Clyde is a large inlet of the sea that extends over 100 km into Scotland\u27s west coast. METHODS: We compiled detailed fisheries landings data for this area and combined them with historical accounts to build a picture of change due to fishing activity over the last 200 years. FINDINGS: In the early 19th century, prior to the onset of industrial fishing, the Firth of Clyde supported diverse and productive fisheries for species such as herring (Clupea harengus, Clupeidae), cod (Gadus morhua, Gadidae), haddock (Melanogrammus aeglefinus, Gadidae), turbot (Psetta maxima, Scophthalmidae) and flounder (Platichthys flesus, Pleuronectidae). The 19th century saw increased demand for fish, which encouraged more indiscriminate methods of fishing such as bottom trawling. During the 1880s, fish landings began to decline, and upon the recommendation of local fishers and scientists, the Firth of Clyde was closed to large trawling vessels in 1889. This closure remained in place until 1962 when bottom trawling for Norway lobster (Nephrops norvegicus, Nephropidae) was approved in areas more than three nautical miles from the coast. During the 1960s and 1970s, landings of bottomfish increased as trawling intensified. The trawl closure within three nautical miles of the coast was repealed in 1984 under pressure from the industry. Thereafter, bottomfish landings went into terminal decline, with all species collapsing to zero or near zero landings by the early 21st century. Herring fisheries collapsed in the 1970s as more efficient mid-water trawls and fish finders were introduced, while a fishery for mid-water saithe (Pollachius virens, Gadidae) underwent a boom and bust shortly after discovery in the late 1960s. The only commercial fisheries that remain today are for Nephrops and scallops (Pecten maximus, Pectinidae). SIGNIFICANCE: The Firth of Clyde is a marine ecosystem nearing the endpoint of overfishing, a time when no species remain that are capable of sustaining commercial catches. The evidence suggests that trawl closures helped maintain productive fisheries through the mid-20th century, and their reopening precipitated collapse of bottomfish stocks. We argue that continued intensive bottom trawling for Nephrops with fine mesh nets will prevent the recovery of other species. This once diverse and highly productive environment will only be restored if trawl closures or other protected areas are re-introduced. The Firth of Clyde represents at a small scale a process that is occurring ocean-wide today, and its experience serves as a warning to others
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