699 research outputs found
Database for structural steel experiments under a distributed collaboration environment
Due to the high requirements of civil infrastructures against the earthquake in Japan, a great number of research organizations have been conducting the structural steel experiments, in particular the seismic tests such as the cyclic loading test and the pseudo-dynamic test, for many years to determine the seismic performances of steel structures. However, the original test data gained by most research organizations are not well stored in an appropriate manner for distribution and possible usage of others. Although a Numerical Database of Steel Structures (NDSS) was developed some years ago to preserve and share experimental data of the ultimate strength tests acquired at Nagoya University, it was not easy to access this database from other computer platform due to the lack of the support of proper communication media. With the rapid development of information networks and their browsers, structural engineers and researchers are able to exchange various types of test data through Internet. This paper presents the development of a distributed collaborative database system for structural steel experiments. The database is made available on the World-Wide Web, and the Java language enables the interactive retrieval efficiently. The applications of the developed database system for the retrieval of experimental data and seismic numerical analysis are validated in the form of examples.<br /
Clustering of Emission-line Stars in the W5E HII region
We have made a new survey of emission-line stars in the W5E HII region to
investigate the population of PMS stars near the OB stars by using the Wide
Field Grism Spectrograph 2 (WFGS2). A total of 139 H-alpha emission stars were
detected and their g'i'-photometry was performed. The spatial distribution of
them shows three aggregates, i.e., two aggregates near the bright-rimmed clouds
at the edge of W5E HII region (BRC 13 and BRC 14) and one near the exciting O7V
star. The age and mass of each H-alpha star were estimated from the extinction
corrected color-magnitude diagram and theoretical evolutionary tracks. We
found, for the first time in this region, that the young stars near the
exciting star are systematically older (4 Myr) than those near the edge of the
HII region (1 Myr). This result supports that the formation of stars proceed
sequentially from the center of HII region to the eastern bright rim. We
further suggest a possibility that the birth of low mass stars near the
exciting star of HII region precede the production of massive OB stars in the
pre-existing molecular cloud.Comment: 16 pages, 7 figures, 3 tables, accepted for publication in PAS
Discotic liquid crystals of transition metal complexes 48: Synthesis of novel phthalocyanine-fullerene dyads and effect of a methoxy group on their clearing points
In our previous work, we could successfully synthesize the 1:1 phthalocyanine-fullerene (Pc-C-60) dyads, (OFbaC(60))PcCu(OCH3) 2, in very high yields (81 similar to 96%) by using Prato reaction. In this study, we have prepared novel Pc-C-60 dyads, (OFbaC(60)) PcM (M = Co (a), Ni (b), Cu (c), metal free (d)) 3a-3d without the methoxy group. The target Pc-C-60 dyads 3a-3d could be successfully synthesized in good yields also by Prato reaction. It is surprising for us that removal of a very small methoxy group from the big (OFbaC(60))PcCu(OCH3) molecule (2) significantly lowers the cp of (OFbaC(60))PcCu (3c) by about 70 degrees C in comparison with that of 2 having the methoxy group. Very interestingly, each of the novel dyads 3a-3d synthesized here shows perfect homeotropic alignment in the tetragonal columnar phase (Col(tet)). Moreover, it is noteworthy that 3c and 3d show only one Col(tet.o) mesophase having ordered stacking distance with perfect homeotropic alignment. Such simple phase transition can contribute to maintain stable performance in wide temperature range, when they will be applied to organic thin film solar cells.ArticleJOURNAL OF PORPHYRINS AND PHTHALOCYANINES. 17(4):264-282 (2013)journal articl
Pre-DECIGO can get the smoking gun to decide the astrophysical or cosmological origin of GW150914-like binary black holes
Pre-DECIGO consists of three spacecraft arranged in an equilateral triangle
with 100km arm lengths orbiting 2000km above the surface of the earth. It is
hoped that the launch date will be in the late 2020s.
Pre-DECIGO has one clear target: binary black holes (BBHs) like GW150914 and
GW151226. Pre-DECIGO can detect BBH mergers up to
redshift . The cumulative event rate is in the Pop III origin model of BBHs like GW150914, and it
saturates at , while in the primordial BBH (PBBH) model, the
cumulative event rate is at
even if only of the dark matter consists of PBHs, and it is
still increasing at . In the Pop I/II model of BBHs, the cumulative event
rate is and it saturates at . We present the requirements on orbit accuracy, drag free techniques, laser
power, frequency stability, and interferometer test mass. For BBHs like
GW150914 at 1Gpc, SNR is achieved with the definition of Pre-DECIGO in
the Hz band. Pre-DECIGO can measure the mass spectrum and the
-dependence of the merger rate to distinguish various models of BBHs like
GW150914.
Pre-DECIGO can also predict the direction of BBHs at with an accuracy
of and a merging time accuracy of s at about a
day before the merger so that ground-based GW detectors further developed at
that time as well as electromagnetic follow-up observations can prepare for the
detection of merger in advance. For intermediate mass BBHs at a large redshift
, the QNM frequency after the merger can be within the Pre-DECIGO band
so that the ringing tail can also be detectable to confirm the Einstein theory
of general relativity with SNR.
[abridged]Comment: 17 pages, 10 figures, added some references, modifications to match
the published version in PTE
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