1,336 research outputs found

    Leadership Behaviour and Upward Feedback: Findings from a Longitudinal Intervention

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    A sample of 48 managers and 308 staff members of a community health care organization took part in a study to investigate the influence of participating in an upward feedback program on leadership behaviour, both as indicated be self-ratings and subordinates’ ratings. The research design consisted of three measurement points within one year. The intervention included managers receiving upward feedback and a management skills workshop. The results showed a negative effect of the program on leadership behaviour as rated by the staff. Furthermore, managers reduced their self-ratings in the condition where they participated in both a feedback session and an management skills workshop.Management;Leadership Behaviour;Self-rating;Upward Feedback

    Effects of upward feedback on leadership behaviour toward subordinates

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    Purpose - To investigate the influence of participating in an upward feedback program on leadership behaviour, both as indicated be self-ratings and subordinates' ratings. Design/methodology/approach - The research design consisted of two measurement points within six months. The program included managers receiving an upward feedback report and a short workshop to facilitate interpretation. A sample of 45 managers and 308 staff members of a community health care organization took part. Findings - The study showed three results. First, managers lack insight into the real impact of their behavior. Second, only a small positive effect was found of the upward feedback program on the leadership behaviour as rated by their staff in terms of valuing diversity. Third, the managers' self-ratings of Presenting feedback, Fairness and Integrity & respect decreased between Time 1 and Time 2. Originality/value - The study points towards the need for HRM professionals to carefully implement upward feedback programs in order to have a real impact on the development of managers

    Numerical Methods in Cosmological Global Texture Simulations

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    Numerical simulations of the evolution of a global topological defect field have two characteristic length scales --- one macrophysical, of order the field correlation length, and the other microphysical, of order the field width. The situation currently of most interest to particle cosmologists involves the behaviour of a GUT-scale defect field at the epoch of decoupling, where the ratio of these scales is typically of order 105010^{50}. Such a ratio is unrealisable in numerical work, and we consider the approximations which may be employed to deal with this. Focusing on the case of global texture we outline the implementation of the associated algorithms, and in particular note the subtleties involved in handling texture unwinding events. Comparing the results in each approach then establishes that, subject to certain constraints on the minimum grid resolution, the methods described are both robust and consistent with one another.Comment: LaTeX, IMPERIAL/TP/93-94/2

    Simulating Calibration and Beam Systematics for a Future CMB Space Mission with the TOAST Package

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    We address in this work the instrumental systematic errors that can potentially affect the forthcoming and future Cosmic Microwave Background experiments aimed at observing its polarized emission. In particular, we focus on the systematics induced by the beam and calibration, which are considered the major sources of leakage from total intensity measurements to polarization. We simulated synthetic data sets with Time-Ordered Astrophysics Scalable Tools, a publicly available simulation and data analysis package. We also propose a mitigation technique aiming at reducing the leakage by means of a template fitting approach. This technique has shown promising results reducing the leakage by 2 orders of magnitude at the power spectrum level when applied to a realistic simulated data set of the LiteBIRD satellite mission

    Leadership Behaviour and Upward Feedback: Findings from a Longitudinal Intervention

    Get PDF
    A sample of 48 managers and 308 staff members of a community health care organization took part in a study to investigate the influence of participating in an upward feedback program on leadership behaviour, both as indicated be self-ratings and subordinates’ ratings. The research design consisted of three measurement points within one year. The intervention included managers receiving upward feedback and a management skills workshop. The results showed a negative effect of the program on leadership behaviour as rated by the staff. Furthermore, managers reduced their self-ratings in the condition where they participated in both a feedback session and an management skills workshop

    PReBeaM for Planck: A Polarized Regularized Beam Deconvolution Map-Making Method

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    We describe a maximum likelihood regularized beam deconvolution map-making algorithm for data from high resolution, polarization sensitive instruments, such as the Planck data set. The resulting algorithm, which we call PReBeaM, is pixel-free and solves for the map directly in spherical harmonic space, avoiding pixelization artifacts. While Fourier methods like ours are expected to work best when applied to smooth, large-scale asymmetric beam systematics (such as far-side lobe effects) we show that our m-truncated spherical harmonic representation of the beam results in negligible reconstruction error -- even for m as small as 4 for a polarized elliptically asymmetric beam. We describe a hybrid OpenMP/MPI parallelization scheme which allows us to store and manipulate the time-ordered data from instruments with arbitrary scanning strategy. Finally, we apply our technique to noisy data and show that it succeeds in removing visible power spectrum artifacts without generating excess noise on small scales.Comment: 12 pages, 8 figures, submitted to ApJS. Full paper with high resolution figures is available at http://www.astro.uiuc.edu/~carmitag/prebeam

    On The Absence Of Open Strings In A Lattice-Free Simulation Of Cosmic String Formation

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    Lattice-based string formation algorithms can, at least in principle, be reduced to the study of the statistics of the corresponding aperiodic random walk. Since in three or more dimensions such walks are transient this approach necessarily generates a population of open strings. To investigate whether open strings are an artefact of the lattice we develop an alternative lattice-free simulation of string formation. Replacing the lattice with a graph generated by a minimal dynamical model of a first order phase transition we obtain results consistent with the hypothesis that the energy density in string is due to a scale-invariant Brownian distribution of closed loops alone.Comment: 9 pages ReVTeX, 1 Postscript figure, minor changes for publicatio

    On Random Bubble Lattices

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    We study random bubble lattices which can be produced by processes such as first order phase transitions, and derive characteristics that are important for understanding the percolation of distinct varieties of bubbles. The results are relevant to the formation of topological defects as they show that infinite domain walls and strings will be produced during appropriate first order transitions, and that the most suitable regular lattice to study defect formation in three dimensions is a face centered cubic lattice. Another application of our work is to the distribution of voids in the large-scale structure of the universe. We argue that the present universe is more akin to a system undergoing a first-order phase transition than to one that is crystallizing, as is implicit in the Voronoi foam description. Based on the picture of a bubbly universe, we predict a mean coordination number for the voids of 13.4. The mean coordination number may also be used as a tool to distinguish between different scenarios for structure formation.Comment: several modifications including new abstract, comparison with froth models, asymptotics of coordination number distribution, further discussion of biased defects, and relevance to large-scale structur

    Determining Foreground Contamination in CMB Observations: Diffuse Galactic Emission in the MAXIMA-I Field

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    Observations of the CMB can be contaminated by diffuse foreground emission from sources such as Galactic dust and synchrotron radiation. In these cases, the morphology of the contaminating source is known from observations at different frequencies, but not its amplitude at the frequency of interest for the CMB. We develop a technique for accounting for the effects of such emission in this case, and for simultaneously estimating the foreground amplitude in the CMB observations. We apply the technique to CMB data from the MAXIMA-1 experiment, using maps of Galactic dust emission from combinations of IRAS and DIRBE observations, as well as compilations of Galactic synchrotron emission observations. The spectrum of the dust emission over the 150--450 GHz observed by MAXIMA is consistent with preferred models but the effect on CMB power spectrum observations is negligible.Comment: 19 pages, 8 figures, accepted for publication in the Astrophysical Journal. Monor changes to match the published versio

    Making Maps Of The Cosmic Microwave Background: The MAXIMA Example

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    This work describes Cosmic Microwave Background (CMB) data analysis algorithms and their implementations, developed to produce a pixelized map of the sky and a corresponding pixel-pixel noise correlation matrix from time ordered data for a CMB mapping experiment. We discuss in turn algorithms for estimating noise properties from the time ordered data, techniques for manipulating the time ordered data, and a number of variants of the maximum likelihood map-making procedure. We pay particular attention to issues pertinent to real CMB data, and present ways of incorporating them within the framework of maximum likelihood map-making. Making a map of the sky is shown to be not only an intermediate step rendering an image of the sky, but also an important diagnostic stage, when tests for and/or removal of systematic effects can efficiently be performed. The case under study is the MAXIMA data set. However, the methods discussed are expected to be applicable to the analysis of other current and forthcoming CMB experiments.Comment: Replaced to match the published version, only minor change
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