537 research outputs found
Formability evaluation of double layer circular tube as a device with energy absorption capacity
Recently, earthquakes frequently occur in Japan. It is desired to promote seismic isolation technology of building. It has been found that newly designed composite material filled with low rigidity material to high rigidity material has significant energy absorbing capacity. However, it must have higher energy absorption capacity in order to respond to a large scale earthquake. Therefore, we have proposed an energy absorbing device with a double layer circular tube as a cell. In previous work, it has been shown that hysteresis occurs and absorbs the energy by friction that is generated between the outer layer and the inner layer. It is effective when inside shape of inner layer is defined as floral pattern. In this study, we considered to form the inner layer circular tube by forward and backward extrusion and to assemble with the outer layer circular tube at the same time. After forming, it is necessary to generate hysteresis around the entire circumference of the circular tube. Ideally, the inner layer circular tube is tightened to the outer layer circular tube. In this research, it was aimed to know the contact state between the outer layer and the inner layer after forming. Therefore, the influence of the presence or absence of the outer layer circular tube on formability was investigated. As a result, there was a tendency for large elastic strain to remain at the contact portion between the circular tubes when the outer layer circular tube was set. This means that the outer layer circular tube hinders elastic recovery of the inner layer circular tube. Therefore, it was confirmed that the inner layer circular tube was tightened by the outer layer circular tube. The same result was obtained when the inner shape of the inner layer circular tube was a flower pattern
Estimating topological entropy of multidimensional nonlinear cellular automata
Cellular automata are discrete dynamical systems whose configurations are determined by local rules acting on each cell in synchronous. Topological entoropy is a tool for measuring the complexity of these dynamical systems. In this paper we estimate topological entropy of a two-dimensional nonlinear cellular automaton. The method we use is that a one-dimensional cellular automaton with positive topological entoropy is “naturally” embedded into the twodimensional cellular automaton. Hence we obtain a multidimensional cellular automaton with infinite topological entoropy
Soft and Hard X-Ray Emissions from the Anomalous X-ray Pulsar 4U 0142+61 Observed with Suzaku
The anomalous X-ray pulsar 4U 0142+61 was observed with Suzaku on 2007 August
15 for a net exposure of -100 ks, and was detected in a 0.4 to ~70 keV energy
band. The intrinsic pulse period was determined as 8.68878 \pm 0.00005 s, in
agreement with an extrapolation from previous measurements. The broadband
Suzaku spectra enabled a first simultaneous and accurate measurement of the
soft and hard components of this object by a single satellite. The former can
be reproduced by two blackbodies, or slightly better by a resonant cyclotron
scattering model. The hard component can be approximated by a power-law of
photon index \Gamma h ~0.9 when the soft component is represented by the
resonant cyclotron scattering model, and its high-energy cutoff is constrained
as >180 keV. Assuming an isotropic emission at a distance of 3.6 kpc, the
unabsorbed 1-10 keV and 10-70 keV luminosities of the soft and hard components
are calculated as 2.8e+35 erg s^{-1} and 6.8e+34 erg s^{-1}, respectively.
Their sum becomes ~10^3 times as large as the estimated spin-down luminosity.
On a time scale of 30 ks, the hard component exhibited evidence of variations
either in its normalization or pulse shape.Comment: 24 pages, 8 figures, accepted for publication in Publications of the
Astronomical Society of Japa
Metallicity of the Fossil Group NGC 1550 Observed with Suzaku
We studied the temperature and metal abundance distributions of the
intra-cluster medium (ICM) in a group of galaxies NGC 1550 observed with
Suzaku. The NGC 1550 is classified as a fossil group, which have few bright
member galaxies except for the central galaxy. Thus, such a type of galaxy is
important to investigate how the metals are enriched to the ICM. With the
Suzaku XIS instruments, we directly measured not only Si, S, and Fe lines but
also O and Mg lines and obtained those abundances to an outer region of ~0.5
r_180 for the first time, and confirmed that the metals in the ICM of such a
fossil group are indeed extending to a large radius. We found steeper gradients
for Mg, Si, S, and Fe abundances, while O showed almost flat abundance
distribution. Abundance ratios of alpha-elements to Fe were similar to those of
the other groups and poor clusters. We calculated the number ratio of type II
to type Ia supernovae for the ICM enrichment to be 2.9 +- 0.5 within 0.1 r_180,
and the value was consistent with those for the other groups and poor clusters
observed with Suzaku. We also calculated metal mass-to-light ratios (MLRs) for
Fe, O and Mg with B-band and K-band luminosities of the member galaxies of NGC
1550. The derived MLRs were comparable to those of NGC 5044 group in the r<0.1
r_180 region, while those of NGC 1550 are slightly higher than those of NGC
5044 in the outer region.Comment: 11 pages, 7 figures, accepted for publication in PAS
Postoperative Acute Exacerbation of IPF after Lung Resection for Primary Lung Cancer
Idiopathic pulmonary fibrosis (IPF) is characterized by slowly progressive respiratory dysfunction. Nevertheless, some IPF patients experience acute exacerbations generally characterized by suddenly worsening and fatal respiratory failure with new lung opacities and pathological lesions of diffuse alveolar damage. Acute exacerbation of idiopathic pulmonary fibrosis (AEIPF) is a fatal disorder defined by rapid deterioration of IPF. The condition sometimes occurs in patients who underwent lung resection for primary lung cancer in the acute and subacute postoperative phases. The exact etiology and pathogenesis remain unknown, but the condition is characterized by diffuse alveolar damage superimposed on a background of IPF that probably occurs as a result of a massive lung injury due to some unknown factors. This systematic review shows that the outcome, however, is poor, with postoperative mortality ranging from 33.3% to 100%. In this paper, the etiology, risk factors, pathogenesis, therapy, prognosis, and predictors of postoperative AEIPF are described
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