2,973 research outputs found
New Zealand contributions to the global earthquake model’s earthquake consequences database (GEMECD)
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
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
Rotating Black Holes at Future Colliders. III. Determination of Black Hole Evolution
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 and Related Approximations
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
. The coupled-cluster approximations we employ go significantly
beyond the diagrammatic content of state-of-the-art theory. We compare our
calculations extensively to and -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
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
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 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 and singularity spectrum
. We derive a relation between and , 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 of the probability distribution of
\delta_{\V{r}}\omega, the difference between the vorticity at two points
separated by a distance . Our numerical simulations are done on a grid.Comment: 18 pages, 17 figure
Bounding biomass in the Fisher equation
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
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.
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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