5,225 research outputs found

    Glasgow time signals

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    From 1859 to 1864, both visual and audio one o’clock time signals operated in Glasgow. Although the University carried a remit to provide the city’s time, following convoluted processes of establishment, a local chronometer-maker operated a time ball for 4 years. Towards the end of the period, time guns were triggered by telegraph from the Royal Observatory Edinburgh. Both exercises caused aggravation for the University. For the ball, the Professor of Astronomy, John Pringle Nichol, failed to convince the City Council that the “drop” control should originate from the University’s Observatory. For the guns, Robert Grant, the newly appointed Astronomy Chair holder, was aggrieved by the Astronomer Royal for Scotland, Piazzi Smyth, appearing to operate above his station. Rather than having only a once per day reference, both projects were abandoned as the University laid a dedicated telegraph cable from its observatory to control many public clocks and additional clocks with large sweep fingers indicating exact time to the second

    Analysis of free analyte fractions by rapid affinity chromatography

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    The invention is generally directed toward an analytical method to determine the concentration of the free analyte fraction in a sample. More particularly, the method encompasses applying a sample comprising a free and bound analyte fraction to an affinity column capable of selectively extracting the free fraction in the millisecond time domain. The signal generated by the free fraction is then quantified by standard analytical detection techniques. The concentration of the free fraction may then be determined by comparison of its signal with that of a calibration curve depicting the signal of known concentration of the same analyte

    Aircraft electromagnetic compatibility

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    Illustrated are aircraft architecture, electromagnetic interference environments, electromagnetic compatibility protection techniques, program specifications, tasks, and verification and validation procedures. The environment of 400 Hz power, electrical transients, and radio frequency fields are portrayed and related to thresholds of avionics electronics. Five layers of protection for avionics are defined. Recognition is given to some present day electromagnetic compatibility weaknesses and issues which serve to reemphasize the importance of EMC verification of equipment and parts, and their ultimate EMC validation on the aircraft. Proven standards of grounding, bonding, shielding, wiring, and packaging are laid out to help provide a foundation for a comprehensive approach to successful future aircraft design and an understanding of cost effective EMC in an aircraft setting

    The Commercial Implication of Normalization

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    Combining pot, atom and step economy (PASE) in organic synthesis. Synthesis of tetrahydropyran-4-ones

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    The combination of pot, atom and step economy (PASE) in the synthesis of organic molecules of medium complexity can lead to a significant 'greening' of a synthetic route. This is demonstrated by the synthesis of highly substituted tetrahydropyran-4-ones and is quantified by a series of recognised metrics, which demonstrate the efficiency of combining PASE over conventional synthetic strategies

    The Impact of Cell Phones and BAC Laws on Motor Vehicle Fatality Rates

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    This paper develops a set of models for the determinants of automobile fatalities with particular attention devoted to the effects of increased cell phone usage. Cell phones have been associated with both life-taking and life-saving properties. However, prior statistical evaluations of the effects of cell phones have led to fragile results. We develop in this paper econometric models using time series data, allowing for polynomial structures of the regressors. The models are evaluated with a set of specification error tests providing reliable estimates of the effects of the various policy and driving related variables evaluated. The statistical results indicate the effect of cell phones is non-monotonic depending on the volume of phones in use, first having a net life-taking effect, then a net life-saving effect, followed finally with a net life-taking effect as the volume of phone use increases.Motor Vehicle Fatalities, Cell Phones, BAC Laws
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