29 research outputs found
Part agent that proposes maintenance actions for a part considering its life cycle
Part of: Seliger, Günther (Ed.): Innovative solutions : proceedings / 11th Global Conference on Sustainable Manufacturing, Berlin, Germany, 23rd - 25th September, 2013. - Berlin: Universitätsverlag der TU Berlin, 2013. - ISBN 978-3-7983-2609-5 (online). - http://nbn-resolving.de/urn:nbn:de:kobv:83-opus4-40276. - pp. 235–240.The transition from a consumption-oriented society to a reuse-based society is needed for the effective use of resources and environmental protection. However, it is difficult for a user to make appropriate decisions for maintenance of his/her parts because of the wide range of choices of action and the huge amount of information required. To support the user's decision and to promote the reuse of parts, we have developed a part agent system that manages information about individual parts throughout their life cycle. A part agent is a network agent that contains the information of its corresponding part and follows the movement of the part via the network throughout its life cycle. This paper describes a new mechanism of a part agent that proposes appropriate maintenance actions for the corresponding part by estimating its expected value, cost, and environmental load based on the predicted information about its life cycle
Spectral transitions of an ultraluminous X-ray source, NGC 2403 Source 3
Suzaku observation of an ultraluminous X-ray source, NGC 2403 Source 3,
performed on 2006 March 16--17, is reported. The Suzaku XIS spectrum of Source
3 was described with a multi-color black-body-like emission from an optically
thick accretion disk. The innermost temperature and radius of the accretion
disk was measured to be keV and km, respectively, where with being the disk inclination. The bolometric
luminosity of the source was estimated to be ergs s. Archival Chandra and XMM-Newton data of the source were
analyzed for long-term spectral variations. In almost all observations, the
source showed multi-color black-body-like X-ray spectra with parameters similar
to those in the Suzaku observation. In only one Chandra observation, however,
Source 3 was found to exhibit a power-law-like spectrum, with a photon index of
, when it was fainter by about than in the
Suzaku observation. The spectral behavior is naturally explained in terms of a
transition between the slim disk state and the "very high" states, both found
in Galactic black hole binaries when their luminosity approach the Eddington
limit. These results are utilized to argue that ultraluminous X-ray sources
generally have significantly higher black-hole masses than ordinary
stellar-mass black holes.Comment: Accepted for PASJ 3nd Suzaku special issu
The ASTRO-H X-ray Observatory
The joint JAXA/NASA ASTRO-H mission is the sixth in a series of highly
successful X-ray missions initiated by the Institute of Space and Astronautical
Science (ISAS). ASTRO-H will investigate the physics of the high-energy
universe via a suite of four instruments, covering a very wide energy range,
from 0.3 keV to 600 keV. These instruments include a high-resolution,
high-throughput spectrometer sensitive over 0.3-2 keV with high spectral
resolution of Delta E < 7 eV, enabled by a micro-calorimeter array located in
the focal plane of thin-foil X-ray optics; hard X-ray imaging spectrometers
covering 5-80 keV, located in the focal plane of multilayer-coated, focusing
hard X-ray mirrors; a wide-field imaging spectrometer sensitive over 0.4-12
keV, with an X-ray CCD camera in the focal plane of a soft X-ray telescope; and
a non-focusing Compton-camera type soft gamma-ray detector, sensitive in the
40-600 keV band. The simultaneous broad bandpass, coupled with high spectral
resolution, will enable the pursuit of a wide variety of important science
themes.Comment: 22 pages, 17 figures, Proceedings of the SPIE Astronomical
Instrumentation "Space Telescopes and Instrumentation 2012: Ultraviolet to
Gamma Ray
The Quiescent Intracluster Medium in the Core of the Perseus Cluster
Clusters of galaxies are the most massive gravitationally-bound objects in
the Universe and are still forming. They are thus important probes of
cosmological parameters and a host of astrophysical processes. Knowledge of the
dynamics of the pervasive hot gas, which dominates in mass over stars in a
cluster, is a crucial missing ingredient. It can enable new insights into
mechanical energy injection by the central supermassive black hole and the use
of hydrostatic equilibrium for the determination of cluster masses. X-rays from
the core of the Perseus cluster are emitted by the 50 million K diffuse hot
plasma filling its gravitational potential well. The Active Galactic Nucleus of
the central galaxy NGC1275 is pumping jetted energy into the surrounding
intracluster medium, creating buoyant bubbles filled with relativistic plasma.
These likely induce motions in the intracluster medium and heat the inner gas
preventing runaway radiative cooling; a process known as Active Galactic
Nucleus Feedback. Here we report on Hitomi X-ray observations of the Perseus
cluster core, which reveal a remarkably quiescent atmosphere where the gas has
a line-of-sight velocity dispersion of 164+/-10 km/s in a region 30-60 kpc from
the central nucleus. A gradient in the line-of-sight velocity of 150+/-70 km/s
is found across the 60 kpc image of the cluster core. Turbulent pressure
support in the gas is 4% or less of the thermodynamic pressure, with large
scale shear at most doubling that estimate. We infer that total cluster masses
determined from hydrostatic equilibrium in the central regions need little
correction for turbulent pressure.Comment: 31 pages, 11 Figs, published in Nature July
Cooling system for the soft X-ray spectrometer onboard Astro-H
金沢大学理工研究域数物科学系The Soft X-ray Spectrometer (SXS) is a cryogenic high resolution X-ray spectrometer onboard the X-ray astronomy satellite Astro-H which will be launched in 2014. The detector array is cooled down to 50 mK using an adiabatic demagnetization refrigerator (ADR). The cooling chain from the room temperature to the ADR heat-sink is composed of superfluid liquid He, a Joule-Thomson cryocooler, and double-stage Stirling cryocoolers. It is designed to keep 30 l of liquid He for more than 5 years in the normal case, and longer than 3 years even if one of the cryocoolers fails. Cryogen-free operation is also possible in the normal case. It is fully redundant from the room temperature to the ADR heat-sink. © 2010 Elsevier Ltd
Hitomi (ASTRO-H) X-ray Astronomy Satellite
The Hitomi (ASTRO-H) mission is the sixth Japanese x-ray astronomy satellite developed by a large international collaboration, including Japan, USA, Canada, and Europe. The mission aimed to provide the highest energy resolution ever achieved at E > 2 keV, using a microcalorimeter instrument, and to cover a wide energy range spanning four decades in energy from soft x-rays to gamma rays. After a successful launch on February 17, 2016, the spacecraft lost its function on March 26, 2016, but the commissioning phase for about a month provided valuable information on the onboard instruments and the spacecraft system, including astrophysical results obtained from first light observations. The paper describes the Hitomi (ASTRO-H) mission, its capabilities, the initial operation, and the instruments/spacecraft performances confirmed during the commissioning operations for about a month