56,343 research outputs found

    Aircrew coordination and decisionmaking: Peer ratings of video tapes made during a full mission simulation

    Get PDF
    Six professionally active, retired captains rated the coordination and decisionmaking performances of sixteen aircrews while viewing videotapes of a simulated commercial air transport operation. The scenario featured a required diversion and a probable minimum fuel situation. Seven point Likert-type scales were used in rating variables on the basis of a model of crew coordination and decisionmaking. The variables were based on concepts of, for example, decision difficulty, efficiency, and outcome quality; and leader-subordin ate concepts such as person and task-oriented leader behavior, and competency motivation of subordinate crewmembers. Five-front-end variables of the model were in turn dependent variables for a hierarchical regression procedure. The variance in safety performance was explained 46%, by decision efficiency, command reversal, and decision quality. The variance of decision quality, an alternative substantive dependent variable to safety performance, was explained 60% by decision efficiency and the captain's quality of within-crew communications. The variance of decision efficiency, crew coordination, and command reversal were in turn explained 78%, 80%, and 60% by small numbers of preceding independent variables. A principle component, varimax factor analysis supported the model structure suggested by regression analyses

    Crew Communication as a Factor in Aviation Accidents

    Get PDF
    The crew communication process is analyzed. Planning and explanation are shown to be well-structured discourse types, described by formal rules. These formal rules are integrated with those describing the other most important discourse type within the cockpit: the command-and-control speech act chain. The latter is described as a sequence of speech acts for making requests (including orders and suggestions), for making reports, for supporting or challenging statements, and for acknowledging previous speech acts. Mitigation level, a linguistic indication of indirectness and tentativeness in speech, was an important variable in several hypotheses, i.e., the speech of subordinates is more mitigated than the speech of superiors, the speech of all crewmembers is less mitigated when they know that they are in either a problem or emergency situation, and mitigation is a factor in failures of crewmembers to initiate discussion of new topics or have suggestions ratified by the captain. Test results also show that planning and explanation are more frequently performed by captains, are done more during crew- recognized problems, and are done less during crew-recognized emergencies. The test results also indicated that planning and explanation are more frequently performed by captains than by other crewmembers, are done more during crew-recognized problems, and are done less during-recognized emergencies

    Strong Limit on a Variable Proton-to-Electron Mass Ratio from Molecules in the Distant Universe

    Full text link
    The Standard Model of particle physics assumes that the so-called fundamental constants are universal and unchanging. Absorption lines arising in molecular clouds along quasar sightlines offer a precise test for variations in the proton-to-electron mass ratio, mu, over cosmological time and distance scales. The inversion transitions of ammonia are particularly sensitive to mu compared to molecular rotational transitions. Comparing the available ammonia spectra observed towards the quasar B0218+357 with new, high-quality rotational spectra, we present the first detailed measurement of mu with this technique, limiting relative deviations from the laboratory value to |dmu/mu| < 1.8x10^{-6} (95% confidence level) at approximately half the Universe's current age - the strongest astrophysical constraint to date. Higher-quality ammonia observations will reduce both the statistical and systematic uncertainties in these measurements.Comment: Science, 20th June 2008. 22 pages, 5 figures (12 EPS files), 2 tables, including Supporting Online Material; v2: Corrected reference for laboratory mu-variation bound

    Paterno v. Laser Spine Institute: Did the New York Court of Appeals\u27 Misapplication of Unjustified Policy Fears Lead to A Miscarriage of Justice and the Creation of Inadequate Precedent for the Proper Use of the Empire State’s Long-Arm Statute?

    Get PDF
    This article discusses CPLR section 302(a)(1) as applied by the New York State Court of Appeals in Paterno v. Laser Spine Institute. The Paterno Court failed to properly apply a statutory jurisdictional analysis by conflating it with a due process inquiry. Also, the Court unnecessarily balanced the interests of the Empire State\u27s citizens in having a forum for access to justice with unjustified policy fears of potential costs to the state from assertions of in personam jurisdiction. Furthermore, the Court\u27s policy focus4 on the protection of medical doctors from lawsuits and the prevention of “floodgate” litigation which would adversely affect the medical profession was not justified by the record and created poor precedent for subsequent judicial application of the state\u27s long-arm statute. This article will examine CPLR section 302(a)(1), under Paterno v. Laser Spine Institute and some of its predecessors, to demonstrate that sometimes overarching policy concerns get in the way of a strict statutory analysis under CPLR section 302(a)(1). We analyze how the Court of Appeals in Paterno conflated the jurisdictional basis and due process analyses and determine that the Court, based on a faulty statutory analysis, erroneously decided that there was no statutory jurisdiction. Our article is divided into six parts. Part II briefly discusses the history of the CPLR and the manner of obtaining jurisdiction through Sections 301 and 302, focusing mainly on long-arm jurisdiction. Part III discusses and analyzes leading cases, which involve the application of CPLR 302 in obtaining personal jurisdiction. Part IV discusses a recent case, Paterno v. Laser Spine Institute, in great detail, and Part V engages in a critical analysis of Paterno with reference to a similar case, Grimaldi v. Guinn. Part VI addresses policy considerations and Part VII concludes with a discussion of how the Paterno Court entangled its jurisdictional analysis and where the Court may be headed with its future application of CPLR section 302(a)(1)

    A human factors methodology for real-time support applications

    Get PDF
    A general approach to the human factors (HF) analysis of new or existing projects at NASA/Goddard is delineated. Because the methodology evolved from HF evaluations of the Mission Planning Terminal (MPT) and the Earth Radiation Budget Satellite Mission Operations Room (ERBS MOR), it is directed specifically to the HF analysis of real-time support applications. Major topics included for discussion are the process of establishing a working relationship between the Human Factors Group (HFG) and the project, orientation of HF analysts to the project, human factors analysis and review, and coordination with major cycles of system development. Sub-topics include specific areas for analysis and appropriate HF tools. Management support functions are outlined. References provide a guide to sources of further information

    Teacher and student perceptions of the development of learner autonomy : a case study in the biological sciences

    Get PDF
    Biology teachers in a UK university expressed a majority view that student learning autonomy increases with progression through university. A minority suggested that pre-existing diversity in learning autonomy was more important and that individuals not cohorts differ in their learning autonomy. They suggested that personal experience prior to university and age were important and that mature students are more autonomous than 18-20 year olds. Our application of an autonomous learning scale (ALS) to four year-groups of biology students confirmed that the learning autonomy of students increases through their time at university but not that mature students are necessarily more autonomous than their younger peers. It was evident however that year of study explained relatively little

    Photometric reverberation mapping of 3C120

    Full text link
    We present the results of a five month monitoring campaign of the local active galactic nuclei (AGN) 3C120. Observations with a median sampling of two days were conducted with the robotic 15cm telescope VYSOS-6 located near Cerro Armazones in Chile. Broad band (B,V) and narrow band (NB) filters were used in order to measure fluxes of the AGN and the H_beta broad line region (BLR) emission line. The NB flux is constituted by about 50% continuum and 50% H_beta emission line. To disentangle line and continuum flux, a synthetic H_beta light curve was created by subtracting a scaled V-band light curve from the NB light curve. Here we show that the H_beta emission line responds to continuum variations with a rest frame lag of 23.6 +/- 1.69 days. We estimate a virial mass of the central black hole M_BH = 57 +/- 27 * 10^6 solar masses, by combining the obtained lag with the velocity dispersion of a single contemporaneous spectrum. Using the flux variation gradient (FVG) method, we determined the host galaxy subtracted rest frame 5100A luminosity at the time of our monitoring campaign with an uncertainty of 10% (L_AGN = 6.94 +/- 0.71* 10^43 ergs^-1). Compared with recent spectroscopic reverberation results, 3C120 shifts in the R_BLR - L_AGN diagram remarkably close to the theoretically expected relation of R-L^0.5. Our results demonstrate the performance of photometric AGN reverberation mapping, in particular for efficiently determining the BLR size and the AGN luminosityComment: 11 pages, 11 figures, Published in Astronomy and Astrophysic

    To What Extent are Frontline Statutory Social Workers Employing Their Discretion in the Post- Munro Review World of Child Protection?

    Get PDF
    In May 2011, Eileen Munro concluded her review of the English child protection system. Within, she identified obstacles which she believed were hindering the realisation of an ‘effective’ and ‘child-centred’ system. This included the ‘risk’ associated with the social worker’s discretionary space, leading managers to restrict, and practitioners to minimise, opportunities for frontline discretion. It was on this basis that Munro called for reform of the system, so that social workers would be better able and motivated to exercise their discretion in the best interests of the individual child. It is also in these terms that the author set out to explore the degree to which social workers are employing their discretion within the contemporary child protection system. This thesis reports on the results of a qualitative mixed methods case study of one local authority’s child protection team. The focus of enquiry pertained to the extent and nature of the discretionary space encountered; whether social workers were willing to employ discretion within different contexts; and the factors that were understood to be impacting upon discretionary space and choice. The research comprised of an iterative design, incorporating focus group, questionnaire, interview, observation and documentary analysis. The main findings were that social workers were experiencing discretionary space in a de jure, de facto and entrepreneurial sense; that practitioners were more likely to choose to exercise their discretion within the managerially endorsed space; and that a series of systemic factors were continuing to impede both the opportunities for, and propensity to choose, discretion. Ultimately, whilst the research provides some evidence in favour of Munro’s image for discretion within the system, the identification of continued barriers leads to the thesis’ conclusion that further reform may be required if child protection social workers are to more consistently employ their discretion in the interests of the individual child
    • 

    corecore