396 research outputs found

    Fabrication of electron beam generated, chirped, phase mask (1070 . 11 – 1070 . 66 nm) for fiber Bragg grating dispersion compensator

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    We report on the fabrication of a chirped, phase mask that was used to create a fiber Bragg grating(FBG)device for the compensation of chromatic dispersion in longhaul optical transmission networks.Electron beamlithography was used to expose the grating onto a resist-coated quartz plate. After etching, this phase mask was used to holographically expose an index grating into the fiber core [K. O. Hill, F. Bilodeau, D. C. Johnson, and J. Albert, Appl. Phys. Lett.62, 1035 (1993)]. The linear increase in the grating period, “chirp,” is only 0.55 nm over the 10 cm grating. This is too small to be defined by computer aided design and a digital deflection system. Instead, the chirp was incorporated by repeatedly rescaling the analog electronics used for field size calibration. Special attention must be paid to minimize any field stitching and exposure artifacts. This was done by using overlapping fields in a “voting” method. As a result, each grating line is exposed by the accumulation of three overlapping exposures at 1/3 dose. This translates any abrupt stitching error into a small but uniform change in the line-to-space ratio of the grating. The phase mask was used with the double-exposure photoprinting technique [K. O. Hill, F. Bilodeau, B. Malo, T. Kitagawa, S. ThĂ©riault, D. C. Johnson, J. Albert, and K. Takiguchi, Opt. Lett. 19, 1314 (1994)]: a KrF excimer laser holograp

    Generic competences for the IT knowledge workers: a study from the field.

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    Proceedings of: Third World Summit on the Knowledge Society (WSKS 2010), Corfu, Greece, September 22-24, 2010This paper aims to identify generic competency levels relevant to a particular kind of knowledge workers: software engineers. Based on previous works, and in particular in the description of a professional career, authors review of the literature related to the characterization of the labor force in the Software Engineering (SE) domain. Subsequently, using a quantitative analysis based on investigative surveys administered to a number of representative professionals, authors provide with a generic competency ladder adapted to the given career description.Publicad

    Gossip in organisations: Contexts, consequences and controversies

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    This article examines the key themes surrounding gossip including its contexts, the various outcomes (positive and negative) of gossip as well as a selection of challenges and controversies. The challenges which are highlighted revolve around definitional issues, methodological approaches, and ethical considerations. Our analysis suggests that the characteristics and features of gossip lend itself to a process-oriented approach whereby the beginning and, particularly, end points of gossip are not always easily identified. Gossip about a subject or person can temporarily disappear only for it to re-surface at some later stage. In addition, questions pertaining to the effects of gossip and ethical-based arguments depend on the nature of the relationships within the gossip triad (gossiper, listener/respondent and target)

    The spiritual organization: critical reflections on the instrumentality of workplace spirituality

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    Authors' draft of article. Final version published by Routledge in Journal of Management, Spirituality and Religion available online at: http://www.tandf.co.uk/journals/titles/14766086.aspThis paper offers a theoretical contribution to the current debate on workplace spirituality by: (a) providing a selective critical review of scholarship, research and corporate practices which treat workplace spirituality in performative terms, that is, as a resource or means to be manipulated instrumentally and appropriated for economic ends; (b) extending Ezioni’s analysis of complex organizations and proposing a new category, the ‘spiritual organization’, and; (c) positing three alternative positions with respect to workplace spirituality that follow from the preceding critique. The spiritual organization can be taken to represent the development of a trajectory of social technologies that have sought, incrementally, to control the bodies, minds, emotions and souls of employees. Alternatively, it might be employed to conceptualize the way in which employees use the workplace as a site for pursuing their own spiritualities (a reverse instrumentalism). Finally, we consider the possible incommensurability of ‘work organization’ and ‘spirituality’ discourses

    Broadband Quantum Enhancement of the LIGO Detectors with Frequency-Dependent Squeezing

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    Quantum noise imposes a fundamental limitation on the sensitivity of interferometric gravitational-wave detectors like LIGO, manifesting as shot noise and quantum radiation pressure noise. Here, we present the first realization of frequency-dependent squeezing in full-scale gravitational-wave detectors, resulting in the reduction of both shot noise and quantum radiation pressure noise, with broadband detector enhancement from tens of hertz to several kilohertz. In the LIGO Hanford detector, squeezing reduced the detector noise amplitude by a factor of 1.6 (4.0 dB) near 1 kHz; in the Livingston detector, the noise reduction was a factor of 1.9 (5.8 dB). These improvements directly impact LIGO's scientific output for high-frequency sources (e.g., binary neutron star postmerger physics). The improved low-frequency sensitivity, which boosted the detector range by 15%-18% with respect to no squeezing, corresponds to an increase in the astrophysical detection rate of up to 65%. Frequency-dependent squeezing was enabled by the addition of a 300-meter-long filter cavity to each detector as part of the LIGO A+ upgrade
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