2,973 research outputs found

    New Zealand contributions to the global earthquake model’s earthquake consequences database (GEMECD)

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    The Global Earthquake Model’s (GEM) Earthquake Consequences Database (GEMECD) aims to develop, for the first time, a standardised framework for collecting and collating geocoded consequence data induced by primary and secondary seismic hazards to different types of buildings, critical facilities, infrastructure and population, and relate this data to estimated ground motion intensity via the USGS ShakeMap Atlas. New Zealand is a partner of the GEMECD consortium and to-date has contributed with 7 events to the database, of which 4 are localised in the South Pacific area (Newcastle 1989; Luzon 1990; South of Java 2006 and Samoa Islands 2009) and 3 are NZ-specific events (Edgecumbe 1987; Darfield 2010 and Christchurch 2011). This contribution to GEMECD represented a unique opportunity for collating, comparing and reviewing existing damage datasets and harmonising them into a common, openly accessible and standardised database, from where the seismic performance of New Zealand buildings can be comparatively assessed. This paper firstly provides an overview of the GEMECD database structure, including taxonomies and guidelines to collect and report on earthquake-induced consequence data. Secondly, the paper presents a summary of the studies implemented for the 7 events, with particular focus on the Darfield (2010) and Christchurch (2011) earthquakes. Finally, examples of specific outcomes and potentials for NZ from using and processing GEMECD are presented, including: 1) the rationale for adopting the GEM taxonomy in NZ and any need for introducing NZ-specific attributes; 2) a complete overview of the building typological distribution in the Christchurch CBD prior to the Canterbury earthquakes and 3) some initial correlations between the level and extent of earthquake-induced physical damage to buildings, building safety/accessibility issues and the induced human casualtie

    Multifractality and scale invariance in human heartbeat dynamics

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    Human heart rate is known to display complex fluctuations. Evidence of multifractality in heart rate fluctuations in healthy state has been reported [Ivanov et al., Nature {\bf 399}, 461 (1999)]. This multifractal character could be manifested as a dependence on scale or beat number of the probability density functions (PDFs) of the heart rate increments. On the other hand, scale invariance has been recently reported in a detrended analysis of healthy heart rate increments [Kiyono et al., Phys. Rev. Lett. {\bf 93}, 178103 (2004)]. In this paper, we resolve this paradox by clarifying that the scale invariance reported is actually exhibited by the PDFs of the sum of detrended healthy heartbeat intervals taken over different number of beats, and demonstrating that the PDFs of detrended healthy heart rate increments are scale dependent. Our work also establishes that this scale invariance is a general feature of human heartbeat dynamics, which is shared by heart rate fluctuations in both healthy and pathological states

    Comparison of Conditional Average Using Threshold and Template Methods for Quasi-Periodic Phenomena in Plasmas

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    Rotating Black Holes at Future Colliders. III. Determination of Black Hole Evolution

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    TeV scale gravity scenario predicts that the black hole production dominates over all other interactions above the scale and that the Large Hadron Collider will be a black hole factory. Such higher dimensional black holes mainly decay into the standard model fields via the Hawking radiation whose spectrum can be computed from the greybody factor. Here we complete the series of our work by showing the greybody factors and the resultant spectra for the brane localized spinor and vector field emissions for arbitrary frequencies. Combining these results with the previous works, we determine the complete radiation spectra and the subsequent time evolution of the black hole. We find that, for a typical event, well more than half a black hole mass is emitted when the hole is still highly rotating, confirming our previous claim that it is important to take into account the angular momentum of black holes.Comment: typoes in eqs(82)-(84) corrected; version to appear in Phys. Rev. D; references and a footnote added; same manuscript with high resolution embedded figures available on http://www.gakushuin.ac.jp/univ/sci/phys/ida/paper

    Spectral Functions of the Uniform Electron Gas via Coupled-Cluster Theory and Comparison to the GWGW and Related Approximations

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    We use, for the first time, ab initio coupled-cluster theory to compute the spectral function of the uniform electron gas at a Wigner-Seitz radius of rs=4r_\mathrm{s}=4. The coupled-cluster approximations we employ go significantly beyond the diagrammatic content of state-of-the-art GWGW theory. We compare our calculations extensively to GWGW and GWGW-plus-cumulant theory, illustrating the strengths and weaknesses of these methods in capturing the quasiparticle and satellite features of the electron gas. Our accurate calculations further allow us to address the long-standing debate over the occupied bandwidth of metallic sodium. Our findings indicate that the future application of coupled-cluster theory to condensed phase material spectra is highly promising.Comment: 6 pages, 2 figure

    Heavy Higgs at Tevatron and LHC in Universal Extra Dimension Models

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    Universal Extra Dimension (UED) models tend to favor a distinctively heavier Higgs mass than in the Standard Model (SM) and its supersymmetric extensions when the Kaluza-Klein (KK) scale is not much higher than the electroweak one, which we call the weak scale UED, in order to cancel the KK top contributions to the T-parameter. Such a heavy Higgs, whose production through the gluon fusion process is enhanced by the KK top loops, is fairly model independent prediction of the weak scale UED models regardless of the brane-localized mass structure at the ultraviolet cutoff scale. We study its cleanest possible signature, the Higgs decay into a Z boson pair and subsequently into four electrons and/or muons, in which all the four-momenta of the final states can be measured and both the Z boson masses can be checked. We show that the weak scale UED model may account for the 2sigma excess of this event at ATLAS at the ZZ pair invariant mass around 250GeV, at which scale SM background is sufficiently small and the SM Higgs predicts too few events. We have also studied the Higgs mass 500GeV (and also 700GeV with \sqrt{s}=14TeV) and have found that we can observe significant resonance with the integrated luminosity 10fb^{-1} for six dimensional UED models.Comment: (v1) 36 pages, 9 figures, 6 tables; (v2) Accepted for publication in Phys. Rev. D, factor 2 error in (93) corrected, comments and references added, figures redrawn; (v3) Minor changes including typo corrections in eq.(15), final version appearing in PR

    Intermittency in Two-Dimensional Turbulence with Drag

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    We consider the enstrophy cascade in forced two-dimensional turbulence with a linear drag force. In the presence of linear drag, the energy wavenumber spectrum drops with a power law faster than in the case without drag, and the vorticity field becomes intermittent, as shown by the anomalous scaling of the vorticity structure functions. Using a previous theory, we compare numerical simulation results with predictions for the power law exponent of the energy wavenumber spectrum and the scaling exponents of the vorticity structure functions ζ2q\zeta_{2q} obtained in terms of the distribution of finite time Lyapunov exponents. We also study, both by numerical experiment and theoretical analysis, the multifractal structure of the viscous enstrophy dissipation in terms of its R\'{e}nyi dimension spectrum DqD_q and singularity spectrum f(α)f(\alpha). We derive a relation between DqD_q and ζ2q\zeta_{2q}, and discuss its relevance to a version of the refined similarity hypothesis. In addition, we obtain and compare theoretically and numerically derived results for the dependence on separation rr of the probability distribution of \delta_{\V{r}}\omega, the difference between the vorticity at two points separated by a distance rr. Our numerical simulations are done on a 4096×40964096 \times 4096 grid.Comment: 18 pages, 17 figure

    Bounding biomass in the Fisher equation

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    The FKPP equation with a variable growth rate and advection by an incompressible velocity field is considered as a model for plankton dispersed by ocean currents. If the average growth rate is negative then the model has a survival-extinction transition; the location of this transition in the parameter space is constrained using variational arguments and delimited by simulations. The statistical steady state reached when the system is in the survival region of parameter space is characterized by integral constraints and upper and lower bounds on the biomass and productivity that follow from variational arguments and direct inequalities. In the limit of zero-decorrelation time the velocity field is shown to act as Fickian diffusion with an eddy diffusivity much larger than the molecular diffusivity and this allows a one-dimensional model to predict the biomass, productivity and extinction transitions. All results are illustrated with a simple growth and stirring model.Comment: 32 Pages, 13 Figure

    Automated Bench-Top Device for Evaluation of Air Fine Purification Filters Efficiency

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    High protective efficiency of filters (fine purification filter-element) used in microbiological laboratories ventilation systems contributes essentially to biological safety provision. Filters are to be tested at bench-top devices prior to application. The existing models of these devices allow to test no more than 8 filters per working day, and require considerable physical efforts. The proposed automated device allows to test 33 filters per working day and decreases considerably workload of the personnel

    Influencia de la temperatura y el tiempo de exposición sobre la germinación y la emergencia de Piptochaetium napostaense (Speg.) Hack.

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    Fire affects not only the vegetation but also the seedbank, the main propagule reservoir of Piptochaetium napostaense. Despite being a well-known species, there is little information of the effect of fire temperatures on the germination and emergence of P. napostaense seeds. In this study, we evaluated the germination and emergence of P. napostaense in response to temperatures and exposure times similar to those observed during a fire. Seeds of P. napostaense were exposed to different treatments that resulted from the combination of six temperature levels (20°C, 70°C, 90°C, 120°C, 140°C and 170°C) and three exposure times (5, 10 and 20 minutes). Results showed that moderate temperaturas (70°C, 90°C) stimulated the germination of P. napostaense and the combination of high temperatures and prolonged exposure times reduced seed viability, and affected seedlings emergence and biomass. Results indicate that germination success of P. napostaense seeds depends on both temperature and exposure time.El fuego no sólo afecta a la vegetación sino también al suelo donde se encuentra el banco de semillas, principal reservorio de propágulos con que cuenta Piptochaetium napostaense (Speg.) Hack. (“flechilla negra”) para su mantenimiento y regeneración. A pesar de ser una especie forrajera estudiada, es escasa la información del efecto de las temperaturas alcanzadas durante un incendio sobre la germinación de las semillas y la emergencia de plántulas de flechilla negra. El objetivo de este trabajo fue evaluar la respuesta de la germinación y la emergencia de esta gramínea a diferentes temperaturas y tiempos de exposición simulando los efectos de un fuego. Las semillas fueron expuestas a diferentes tratamientos que resultaron de la combinación de seis temperaturas (20°C, 70°C, 90°C, 120°C, 140°C y 170°C) y tres tiempos de exposición (5, 10 y 20 min.). Los resultados mostraron que las temperaturas de 70°C y 90°C estimularon la germinación y la combinación temperaturas altas-tiempos de exposición de 10 y 20 min. redujeron la viabilidad de las semillas, afectaron la emergencia y la producción de biomasa de las plántulas de P. napostaense. De los resultados obtenidos podría concluirse que el éxito de la germinación de las semillas de P. napostaense dependerá de la combinación temperatura-tiempo
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