1,320 research outputs found
パーティクル・ボードに関する研究 : (第6報)含脂率およびパーティクル・ディメンションが低比重ボードの材質におよぼす影響について
この論文は国立情報学研究所の学術雑誌公開支援事業により電子化されました
Solar wind dependence of the electron flux variation at geostationary orbit observed by ETS-V
In this study we have examined the relationship between the energetic electron flux at geostationary orbit and the solar wind speed. We have compared the electron flux ( >0.4MeV) observed by the Engineering Test Satellite V (ETS-V) with solar wind speed measurements in the OMNI data set obtained from the National Space Science Data Center (NSSDC). The tendency has been observed for the logarithm of the electron flux to be proportional to the solar wind speed at solar minimum, but scattered at solar maximum. We have found that during the main and recovery phases of magnetic storms occurring at solar minimum, the logarithm of the electron flux is roughly proportional to the solar wind speed. At solar maximum, however, there is no apparent correlation between both these parameters. Moreover, in quiet periods there is also no observable correlation at both solar minimum and maximum. The dependence of the electron flux at geostationary orbit on the solar wind speed is related to recurrent storms caused by high-speed solar wind streams
Geometrical and band-structure effects on phonon-limited hole mobility in rectangular cross-sectional germanium nanowires
We calculated the phonon-limited hole mobility in rectangular cross-sectional [001], [110], [111], and [112]-oriented germanium nanowires, and the hole transport characteristics were investigated. A tight-binding approximation was used for holes, and phonons were described by a valence force field model. Then, scattering probability of holes by phonons was calculated taking account of hole-phonon interaction atomistically, and the linearized Boltzmann's transport equation was solved to calculate the hole mobility at low longitudinal field. The dependence of the hole mobility on nanowire geometry was analyzed in terms of the valence band structure of germanium nanowires, and it was found that the dependence was qualitatively reproduced by considering an average effective mass and the density of states of holes. The calculation revealed that [110] germanium nanowires with large height along the [001] direction show high hole mobility. Germanium nanowires with this geometry are also expected to exhibit high electron mobility in our previous work, and thus they are promising for complementary metal-oxide-semiconductor (CMOS) applications
Solvable model of a phase oscillator network on a circle with infinite-range Mexican-hat-type interaction
We describe a solvable model of a phase oscillator network on a circle with
infinite-range Mexican-hat-type interaction. We derive self-consistent
equations of the order parameters and obtain three non-trivial solutions
characterized by the rotation number. We also derive relevant characteristics
such as the location-dependent distributions of the resultant frequencies of
desynchronized oscillators. Simulation results closely agree with the
theoretical ones
Synapse efficiency diverges due to synaptic pruning following over-growth
In the development of the brain, it is known that synapses are pruned
following over-growth. This pruning following over-growth seems to be a
universal phenomenon that occurs in almost all areas -- visual cortex, motor
area, association area, and so on. It has been shown numerically that the
synapse efficiency is increased by systematic deletion. We discuss the synapse
efficiency to evaluate the effect of pruning following over-growth, and
analytically show that the synapse efficiency diverges as O(log c) at the limit
where connecting rate c is extremely small. Under a fixed synapse number
criterion, the optimal connecting rate, which maximize memory performance,
exists.Comment: 15 pages, 16 figure
An Exact Integration Scheme for Radiative Cooling in Hydrodynamical Simulations
A new scheme for incorporating radiative cooling in hydrodynamical codes is
presented, centered around exact integration of the governing semi-discrete
cooling equation. Using benchmark calculations based on the cooling downstream
of a radiative shock, I demonstrate that the new scheme outperforms traditional
explicit and implicit approaches in terms of accuracy, while remaining
competitive in terms of execution speed.Comment: 7 pages, accepted by ApJS. Revision 2, with error in eqn. 13 fixe
Chemo- and Thermosensory Responsiveness of Grueneberg Ganglion Neurons Relies on Cyclic Guanosine Monophosphate Signaling Elements
Neurons of the Grueneberg ganglion (GG) in the anterior nasal region of mouse pups respond to cool temperatures and to a small set of odorants. While the thermosensory reactivity appears to be mediated by elements of a cyclic guanosine monophosphate (cGMP) cascade, the molecular mechanisms underlying the odor-induced responses are unclear. Since odor-responsive GG cells are endowed with elements of a cGMP pathway, specifically the transmembrane guanylyl cyclase subtype GC-G and the cyclic nucleotide-gated ion channel CNGA3, the possibility was explored whether these cGMP signaling elements may also be involved in chemosensory GG responses. Experiments with transgenic mice deficient for GC-G or CNGA3 revealed that GG responsiveness to given odorants was significantly diminished in these knockout animals. These findings suggest that a cGMP cascade may be important for both olfactory and thermosensory signaling in the GG. However, in contrast to the thermosensory reactivity, which did not decline over time, the chemosensory response underwent adaptation upon extended stimulation, suggesting that the two transduction processes only partially overlap. Copyright (C) 2011 S. Karger AG, Base
Structural and electronic characterization of (2,3(3)) bar-shaped stacking fault in 4H-SiC epitaxial layers
Crystallographic, electronic, and energetic analyses of the (2, 3_3) [or (2, 3, 3, 3) in the standard Zhadanov notation] bar-shaped stacking fault, observed in as-grown 4H-SiC epitaxial layers, are presented. The defect has been identified by means of spatially resolved microphotoluminescence (μ-PL) measurements at different emission wavelengths, focusing on the emission peak at 0.3 eV below the conduction band. Low temperature μ-PL measurements have also been performed. The defect has been identified and characterized using high resolution transmission electron microscopy. Experimental results are correlated and validated by the calculations of the Kohn–Sham electronic band structure and the defect formation energy
Применение криптографических методов шифрования информации
Необходимость технических средств защиты диктуется тем, что Интернет – это источник информации, за который никто не несет ответственности, и вероятность получения из него недостоверной, оскорбительной, пиратской или запрещенной по другим причинам информации весьма велика.The need for technological protection measures dictated by the fact that the Internet - a source of information for which no one is responsible, and the probability of getting out of it inaccurate, abusive, pirated or illegal for other reasons information is very high
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