220 research outputs found

    Adapting cause and effects methodology to your Safety instrumented system (SIS) to reduce human errors from engineering, operations and beyond

    Get PDF
    PresentationA safety instrumented system (SIS) is used to implement one or more Safety Instrumented Functions (SIFs) which are designed to reduce the likelihood of hazardous risk by decreasing the frequency of unwanted events (accidents). The amount of risk reduction that an SIS can provide is represented by its safety integrity level (SIL). The SIS is designed to detect when the process reaches a hazardous condition and respond accordingly to move the process to a safe state, thus preventing the unwanted accident from occurring. Studies indicate however, that over 50% of all SIS failures are related Systematic faults introduced by human error. While many SIS systems boast having SIL 3 certification, it’s often the human interactions that render many of these well intended systems to be essentially idle. A cause and effects methodology is an approach many in the industry are exploring to help reduce human errors throughout the entire safety lifecycle of the SIS

    Examining plausibility of self-report energy intake data: considerations for method selection.

    Get PDF
    Self-reported dietary intake data contain valuable information and have long been used in the development of nutrition programs and policy. Some degree of measurement error is always present in such data. Biological plausibility, assessed by determining whether self-reported energy intake (rEI) reflects physiological status and physical activity level, must be examined and accounted for before drawing conclusions about intake. Methods that may be used to account for plausibility of rEI include crude methods such as excluding participants reporting EIs at the extremes of a range of intake and individualized methods such as statistical adjustment and applying cutoffs that account for the errors associated with within-participant variation in EI and total energy expenditure (TEE). These approaches allow researchers to determine how accounting for under- and overreporting affects study results and to appropriately address misreporting in drawing conclusions with data collected and in interpreting reported research. In selecting a procedure to assess and account for plausibility of intake, there are a number of key considerations, such as resources available, the dietary-report instrument, as well as the advantages and disadvantages of each method. While additional studies are warranted to recommend one procedure as superior to another, researchers should apply one of the available methods to address the issue of implausible rEI. If no method is applied, then at minimum, mean TEE or rEI/TEE should be reported to allow readers to ascertain the degree of misreporting at a gross level and better interpret the data and results provided

    Colour reconnection and Bose-Einstein effects

    Full text link
    Final-state interactions and interference phenomena that could affect the value of the W mass reconstructed from hadronic WW decays at LEP2 are reviewed, and possible areas for future investigation are identified.Comment: 14 pages, 5 figures, LaTeX, uses epsfig. Talk at Phenomenology Workshop on LEP2 Physics, Oxford, April 199

    The effects of nonextensive statistics on fluctuations investigated in event-by-event analysis of data

    Full text link
    We investigate the effect of nonextensive statistics as applied to the chemical fluctuations in high-energy nuclear collisions discussed recently using the event-by-event analysis of data. It turns out that very minuite nonextensitivity changes drastically the expected experimental output for the fluctuation measure. This results is in agreement with similar studies of nonextensity performed recently for the transverse momentum fluctuations in the same reactions.Comment: Revised version, to be published in J. Phys. G (2000

    Broadband classification and statistics of echoes from aggregations of fish measured by long-range, mid-frequency sonar

    Get PDF
    Author Posting. © Acoustical Society of America, 2017. This article is posted here by permission of Acoustical Society of America for personal use, not for redistribution. The definitive version was published in Journal of the Acoustical Society of America 141 (2017): 4354, doi:10.1121/1.4983446.For horizontal-looking sonar systems operating at mid-frequencies (1–10 kHz), scattering by fish with resonant gas-filled swimbladders can dominate seafloor and surface reverberation at long-ranges (i.e., distances much greater than the water depth). This source of scattering, which can be difficult to distinguish from other sources of scattering in the water column or at the boundaries, can add spatio-temporal variability to an already complex acoustic record. Sparsely distributed, spatially compact fish aggregations were measured in the Gulf of Maine using a long-range broadband sonar with continuous spectral coverage from 1.5 to 5 kHz. Observed echoes, that are at least 15 decibels above background levels in the horizontal-looking sonar data, are classified spectrally by the resonance features as due to swimbladder-bearing fish. Contemporaneous multi-frequency echosounder measurements (18, 38, and 120 kHz) and net samples are used in conjunction with physics-based acoustic models to validate this approach. Furthermore, the fish aggregations are statistically characterized in the long-range data by highly non-Rayleigh distributions of the echo magnitudes. These distributions are accurately predicted by a computationally efficient, physics-based model. The model accounts for beam-pattern and waveguide effects as well as the scattering response of aggregations of fish.This research was supported by the U.S. Office of Naval Research, the National Oceanographic Partnership Program, NOAA, WHOI, and the Oceanographer of the U.S. Navy

    Criticality, Fractality and Intermittency in Strong Interactions

    Full text link
    Assuming a second-order phase transition for the hadronization process, we attempt to associate intermittency patterns in high-energy hadronic collisions to fractal structures in configuration space and corresponding intermittency indices to the isothermal critical exponent at the transition temperature. In this approach, the most general multidimensional intermittency pattern, associated to a second-order phase transition of the strongly interacting system, is determined, and its relevance to present and future experiments is discussed.Comment: 15 pages + 2 figures (available on request), CERN-TH.6990/93, UA/NPPS-5-9

    Numerical Confirmation of Late-time t^{1/2} Growth in Three-dimensional Phase Ordering

    Full text link
    Results for the late-time regime of phase ordering in three dimensions are reported, based on numerical integration of the time-dependent Ginzburg-Landau equation with nonconserved order parameter at zero temperature. For very large systems (7003700^3) at late times, t≥150,t \ge 150, the characteristic length grows as a power law, R(t)∼tnR(t) \sim t^n, with the measured nn in agreement with the theoretically expected result n=1/2n=1/2 to within statistical errors. In this time regime R(t)R(t) is found to be in excellent agreement with the analytical result of Ohta, Jasnow, and Kawasaki [Phys. Rev. Lett. {\bf 49}, 1223 (1982)]. At early times, good agreement is found between the simulations and the linearized theory with corrections due to the lattice anisotropy.Comment: Substantially revised and enlarged, submitted to PR

    Multi-boson effects and the normalization of the two-pion correlation function

    Get PDF
    The two-pion correlation function can be defined as a ratio of either the measured momentum distributions or the normalized momentum space probabilities. We show that the first alternative avoids certain ambiguities since then the normalization of the two-pion correlator contains important information on the multiplicity distribution of the event ensemble which is lost in the second alternative. We illustrate this explicitly for specific classes of event ensembles.Comment: 6 pages, three figures,submit to PR

    Swarming in shallow waters

    Get PDF
    A swarm is a collection of separate objects that move autonomously in the same direction in a concerted fashion. This type of behavior is observed in ensembles of various organisms but has proven inherently difficult to realize in artificial chemical systems, where the components have to self-assemble dynamically and, at the same time, propel themselves. This paper describes a class of systems in which millimeter-sized components interact hydrodynamically and organize into dissipative structures that swarm in thin fluid layers. Depending on the geometry of the particles, various types of swarms can be engineered, including ensembles that rotate, follow a "leader", or are pushed in front of a larger particle

    The Grizzly, February 28, 2002

    Get PDF
    Doug Farah Pays a Visit to Ursinus • Ursinus Students in Who\u27s Who List • Mysterious Rash Hits School Children Across the Country • Welcome to the Real World • Xanax Abuse • Controversy in the World of Figure Skating • Opinions: Spring Break; Sprinklers: Where are They?; Italy for a Semester • Experience the Beauty of Spring at the Philadelphia Flower Show • Marisol: A Different but Successful Performance at Ursinus College • Some Hot Tips for an Exciting and Safe Spring Break in Sunny Mexico • Track Team\u27s Results from Haverford • Men\u27s Basketball Falls Short at F&M • Men\u27s Rugby Team Admitted to Eastern Pennsylvania Rugby Union • Kings of the Court • Aivazian says Bye, Bye, Bye to the Division I Competition at UPenn • UC Swimmers Turn Up the Heat in the Water at the 2002 CC Championship Meethttps://digitalcommons.ursinus.edu/grizzlynews/1509/thumbnail.jp
    • …
    corecore