10,271 research outputs found

    Transportation Construction Work-Zone Safety Impact on Time-Related Incentive Contracting Projects

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    Work-zone safety on highway projects continues to be a national concern, and project safety performance is one of the indicators of project success. Many contractors and State Transportation Agencies believe that expedited construction time under incentive contracting contributes to reducing the safety risk of road users traveling through work zones. However, the truth of this belief has never been measured or supported by any statistical evidence. Therefore, this research investigates the statistical relationship between time-related incentive road construction projects and frequency of vehicle crashes in California to understand the impact of time-related incentive provisions on project safety performance. The research team collected incentive and non-incentive project data from the California Department of Transportation. Additionally, vehicle crash data was collected from the California Statewide Integrated Traffic Records System. Using Geographic Information System (GIS) software, the locations of construction projects and crashes at the project locations were then pinpointed on GIS centerline layers. The research team performed statistical analyses to test the relationship between the frequency and characteristics of crashes at incentive project sites and ones at non-incentive project sites before, during, and after construction. Finally, the analysis results for both time-related incentive projects and non-incentive projects were summarized to provide project planners and managers with a better understanding of the impact of time-related incentive contracting on project safety performance

    Cinderella: The study of cross-cultural encounters in pre-modern societies

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    The vast number of Cinderella variants across the world is staggering and almost unfathomable. Hundreds of versions exist all across the world including Africa, Europe, and Asia. Most people are familiar with the modern Cinderella version written by a French author in the 17th century. But unbeknownst to a majority of the population, this story dates back centuries ago from earlier time periods. One of the earliest written accounts of the Cinderella story was found in China about 850-860 A.D and the name of the protagonist was Yeh-hsien, instead of Cinderella. By means of comparative textual analysis, three versions of Cinderella from across the world in pre-modern societies (Egyptian, Indian, & Chinese) will be examined for cultural traces and methods of diffusion. I will then briefly attempt to establish my case from the textual evidence that it is possible to examine evidence for cross-cultural encounters in pre-modern societies

    PID Application: RTLS

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    The Light and Period Variations of the Eclipsing Binary AA Ursae Majoris

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    We present new multiband CCD photometry for AA UMa made on 8 nights between January and March 2009; the RR light curves are the first ever compiled. Historical light curves, as well as ours, display partial eclipses and inverse O'Connell effects with Max I fainter than Max II. Among possible spot models, a cool spot on either of the component stars and its variability with time permit good light-curve representations for the system. A total of 194 eclipse timings over 81 yrs, including our five timings, were used for ephemeris computations. We found that the orbital period of the system has varied due to a periodic oscillation overlaid on an upward parabolic variation. The continuous period increase at a fractional rate of ++1.3×\times1010^{-10} is consistent with that calculated from the W-D code and can be interpreted as a thermal mass transfer from the less to the more massive secondary star at a rate of 6.6×\times108^{-8} M_\odot yr1^{-1}. The periodic component is in satisfactory accord with a light-time effect due to an unseen companion with a period of 28.2 yrs, a semi-amplitude of 0.007 d, and a minimum mass of M3sini3M_3 \sin i_3=0.25 MM_\odot but this period variation could also arise from magnetic activity.Comment: 23 pages, including 5 figures and 8 tables, accepted for publication in PAS
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