805 research outputs found

    Capturing complexity: developing an integrated approach to analysing HRM in SMEs

    Get PDF
    This article presents a framework to evaluate HRM in small and medium-sized enterprises (SMEs), using an open systems theoretical perspective. In presenting an open systems perspective the objective is to overcome the limitations of existing theorising in HRM, in particular to facilitate a move away from the ‘small is beautiful’ versus ‘bleak house’ stereotypes evident in much of the literature concerned with HRM in SMEs. The evidence is drawn from six SMEs operating in the Republic of Ireland, using a case study method. The findings show that a complex interplay of external structural factors and internal dynamics shaped HRM in each of the companies. HRM was not the coherent set of practices typically identified in the literature but rather was often informal and emergent. It is argued that the open systems theoretical framework enables a move beyond mere recognition of the complexity and heterogeneity of HRM in SMEs, towards an understanding, accommodation and explanation of particularistic factors

    Quick divergence but slow convergence during ecotype formation in lake and stream stickleback pairs of variable age

    Get PDF
    When genetic constraints restrict phenotypic evolution, diversification can be predicted to evolve along so-called lines of least resistance. To address the importance of such constraints and their resolution, studies of parallel phenotypic divergence that differ in their age are valuable. Here, we investigate the parapatric evolution of six lake and stream threespine stickleback systems from Iceland and Switzerland, ranging in age from a few decades to several millennia. Using phenotypic data, we test for parallelism in ecotypic divergence between parapatric lake and stream populations and compare the observed patterns to an ancestral-like marine population. We find strong and consistent phenotypic divergence, both among lake and stream populations and between our freshwater populations and the marine population. Interestingly, ecotypic divergence in low-dimensional phenotype space (i.e. single traits) is rapid and seems to be often completed within 100 years. Yet, the dimensionality of ecotypic divergence was highest in our oldest systems and only there parallel evolution of unrelated ecotypes was strong enough to overwrite phylogenetic contingency. Moreover, the dimensionality of divergence in different systems varies between trait complexes, suggesting different constraints and evolutionary pathways to their resolution among freshwater systems

    Sensitivity Studies for Third-Generation Gravitational Wave Observatories

    Full text link
    Advanced gravitational wave detectors, currently under construction, are expected to directly observe gravitational wave signals of astrophysical origin. The Einstein Telescope, a third-generation gravitational wave detector, has been proposed in order to fully open up the emerging field of gravitational wave astronomy. In this article we describe sensitivity models for the Einstein Telescope and investigate potential limits imposed by fundamental noise sources. A special focus is set on evaluating the frequency band below 10Hz where a complex mixture of seismic, gravity gradient, suspension thermal and radiation pressure noise dominates. We develop the most accurate sensitivity model, referred to as ET-D, for a third-generation detector so far, including the most relevant fundamental noise contributions.Comment: 13 pages, 7 picture

    Scientific Potential of Einstein Telescope

    Full text link
    Einstein gravitational-wave Telescope (ET) is a design study funded by the European Commission to explore the technological challenges of and scientific benefits from building a third generation gravitational wave detector. The three-year study, which concluded earlier this year, has formulated the conceptual design of an observatory that can support the implementation of new technology for the next two to three decades. The goal of this talk is to introduce the audience to the overall aims and objectives of the project and to enumerate ET's potential to influence our understanding of fundamental physics, astrophysics and cosmology.Comment: Conforms to conference proceedings, several author names correcte

    Scientific Objectives of Einstein Telescope

    Full text link
    The advanced interferometer network will herald a new era in observational astronomy. There is a very strong science case to go beyond the advanced detector network and build detectors that operate in a frequency range from 1 Hz-10 kHz, with sensitivity a factor ten better in amplitude. Such detectors will be able to probe a range of topics in nuclear physics, astronomy, cosmology and fundamental physics, providing insights into many unsolved problems in these areas.Comment: 18 pages, 4 figures, Plenary talk given at Amaldi Meeting, July 201

    Radio and submillimetre observations of wind structure in zeta Pup

    Get PDF
    We present radio and submillimetre observations of the O4I(n)f star zeta Pup, and discuss structure in the outer region of its wind (~ 10-100 R*). The properties of bremsstrahlung, the dominant emission process at these wavelengths, make it sensitive to structure and allow us to study how the amount of structure changes in the wind by comparing the fluxes at different wavelengths. To look for variability, we acquired 3.6 and 6 cm observations with the Australia Telescope Compact Array (ATCA). We supplemented these with archive observations from the NRAO Very Large Array (VLA). We did not find variability at more than the +- 20 % level. The long integration time does allow an accurate determination of the fluxes at 3.6 and 6 cm. Converting these fluxes into a mass loss rate, we find Mdot = 3.5 x 10^{-6} Msun/yr. This value confirms the significant discrepancy with the mass loss rate derived from the Halpha profile, making zeta Pup an exception to the usually good agreement between Halpha and radio mass loss rates. We also observed zeta Pup at 850 mum with the James Clerk Maxwell Telescope (JCMT) and at 20 cm with the VLA. A smooth wind model shows that the millimetre fluxes are too high compared to the radio fluxes. While recombination of helium in the outer wind cannot be discounted as an explanation, the wealth of evidence for structure strongly suggests this as the explanation for the discrepancy. Model calculations show that the structure needs to be present in the inner ~ 70 R* of the wind, but that it decays significantly, or maybe even disappears, beyond that radius.Comment: 13 pages, 8 figures, to be published in Astronomy and Astrophysic
    • 

    corecore