12,563 research outputs found

    High-resolution dynamical modelling of the Antarctic stratospheric vortex

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    Progress is reported on the high-resolution three-dimensional numerical simulation of flows characteristic of the Antarctic wintertime stratosphere. The numerical model is a modified version of the Reading University sigma-coordinate used previously for tropospheric studies. Physical parameterizations are kept to a minimum in order to concentrate as much computing power as possible on simulating details of the dynamical processes. The major question addressed is whether the features observed in recent high-resolution two-dimensional simulations - namely: (1) the formation of a sharp edge to the vortex (seen in the potential vorticity field), (2) the survival of the polar vortex in a material entity, and (3) the formation of small-scale eddies rough the break-up of tongues of high potential vorticity drawn out from the polar vortex - are realized in three-dimensional simulations

    The impact of generational differences on the workplace

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    Purpose – The aim of this paper is to explore workplace implications of the changing workforce demographic. Design/methodology/approach – The author identifies the different generations in today's workforce. The workplace expectations of the different generations are explored. Findings – Corporate real estate (CRE) managers need to establish the different needs of the different generations. In addition, the CRE manager needs to create an environment that allows all generations to coexist in the same workplace. Practical implications – CRE managers can use the information to assist in alignment of their workplace to the different generational expectations of the workforce. Originality/value – The paper fills a void by evaluating office occupiers' workplace preferences based on age.</p

    Remote water monitoring system

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    A remote water monitoring system is described that integrates the functions of sampling, sample preservation, sample analysis, data transmission and remote operation. The system employs a floating buoy carrying an antenna connected by lines to one or more sampling units containing several sample chambers. Receipt of a command signal actuates a solenoid to open an intake valve outward from the sampling unit and communicates the water sample to an identifiable sample chamber. Such response to each signal receipt is repeated until all sample chambers are filled in a sample unit. Each sample taken is analyzed by an electrochemical sensor for a specific property and the data obtained is transmitted to a remote sending and receiving station. Thereafter, the samples remain isolated in the sample chambers until the sampling unit is recovered and the samples removed for further laboratory analysis

    Impact of workplace connectivity on office productivity

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    This study developed a validated theoretical framework for the evaluation of office productivity which included components to represent both the physical and the behavioural environment. It is proposed that by adopting such an approach, insights into the dynamic nature, or connectivity, of office environments can be established. The main objective of this research was to investigate the effects of the office environment on its occupants perceived productivity. Results are analysed for specific work patterns (Laing et al, 1998), to establish meaning and relationships. In all of the four work patterns evaluated it was found that interaction was perceived to be the component to have the most positive affect on productivity and distraction was perceived to have the most negative. It is proposed that the results in this paper will provide support for the hypothesis that it is the behavioural components of the office environment that have the greatest impact on office productivity

    Conference Summary: HI Science in the Next Decade

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    The atomic hydrogen (HI) 21cm line measures the gas content within and around galaxies, traces the dark matter potential and probes volumes and objects that other surveys do not. Over the next decade, 21cm line science will exploit new technologies, especially focal plane and aperture arrays, and will see the deployment of Epoch of Reionization/Dark Age detection experiments and Square Kilometer Array (SKA) precursor instruments. Several experiments designed to detect and eventually to characterize the reionization history of the intergalactic medium should deliver first results within two-three years time. Although "precision cosmology" surveys of HI in galaxies at z ~ 1 to 3 require the full collecting area of the SKA, a coherent program of HI line science making use of the unique capabilities of both the existing facilities and the novel ones demonstrated by the SKA precursors will teach us how many gas rich galaxies there really are and where they reside and will yield fundamental insight into how galaxies accrete gas, form stars and interact with their environment.Comment: To appear in AIP Conference Proceedings, "The Evolution of Galaxies through the Neutral Hydrogen Window", Feb 1-3 2008, Arecibo, Puerto Rico, eds. R. Minchin & E. Momjian. 8 page

    The ALFALFA Search for (Almost) Dark Galaxies across the HI Mass Function

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    The Arecibo Legacy Fast ALFA (ALFALFA) survey is a second generation blind extragalactic HI survey currently in progess which is exploiting Arecibo's superior sensitivity, angular resolution and digital technology to derive a census of the local HI universe over a cosmologically significant volume. As of the time of this meeting, some 4500 good quality extragalactic HI line sources have been identified in about 15% of the final survey area. ALFALFA is detecting HI masses as low as 10**6 solar masses and as large as 10**10.8 solar masses with positional accuracies typically better than 20", allowing immediate identification of the most probable optical counterparts. Only 3% of all extragalactic HI sources and less than 1% of detections with HI mass 10**9.5 solar masses cannot be identified with a stellar component. Because ALFALFA is far from complete, the discussion here focuses on limitations of past surveys that ALFALFA will overcome because of its greater volume, sensitivity and reduced susceptibility to source confusion and on a sampling of illustrative preliminary results. First ALFALFA results already suggest, in agreement with previous studies, that there does not appear to be a cosmologically significant population of optically dark but HI rich galaxies. ALFALFA promises a wealthy dataset for the exploration of many issues in near-field cosmology and galaxy evolution studies, setting the stage for their extension to higher redshifts in the future with the Square Kilometer Array (SKA).Comment: To appear in Proceedings of IAU Symp #244, "Dark Galaxies and Lost Baryons", June 2007, 10 pages including 5 figure
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