6,280 research outputs found
Power law velocity fluctuations due to inelastic collisions in numerically simulated vibrated bed of powder}
Distribution functions of relative velocities among particles in a vibrated
bed of powder are studied both numerically and theoretically. In the solid
phase where granular particles remain near their local stable states, the
probability distribution is Gaussian. On the other hand, in the fluidized
phase, where the particles can exchange their positions, the distribution
clearly deviates from Gaussian. This is interpreted with two analogies;
aggregation processes and soft-to-hard turbulence transition in thermal
convection. The non-Gaussian distribution is well-approximated by the
t-distribution which is derived theoretically by considering the effect of
clustering by inelastic collisions in the former analogy.Comment: 7 pages, using REVTEX (Figures are inculded in text body)
%%%Replacement due to rivision (Europhys. Lett., in press)%%
Single-crystal growth and magnetic properties of the metallic molybdate pyrochlore Sm2Mo2O7
We have successfully grown cm3-size single crystals of the
metallic-ferromagnet Sm2Mo2O7 by the floating-zone method using an infrared-red
image furnace. The growth difficulties and the remedies found using a 2-mirror
image furnace are discussed. Magnetization studies along the three crystalline
axes of the compound are presented and discussed based on our recent proposal
of an ordered spin-ice ground state for this compoun
AGAINST THE NULL COMPLEMENTIZER ANALYSIS OF JAPANESE RELATIVE CLAUSES
In this paper, I argued that relative clauses in Japanese are IPs, contrary to the proposal that they are CPs headed by a null complementizer. I assumed that the lack of CP is responsible for the inapplicability of embedded topicalization in relative clauses and clausal adnominal modifiers in Japanese, and concluded that whenever they have a complementizer, it must be overt. I also showed that null complementizers must be licensed by an adjacent verb or noun, and demonstrated that relative clauses in Japanese do not have a null complementizer, based on the observation that they need not be adjacent to the head noun. Hence, I proposed that NGC is a result of Agree between a nominal element D and the embedded subject. Also, in order to answer the question why NGC is possible under Agree Closest and why it is blocked when a complementizer appears overtly, I referred to an analysis where the optional T-to-D head movement plays an important role. Under this analysis, the head movement feeds the Agree relation, but it is blocked when C is intervening between T and D.ArticleNanzan Linguistics Special Issue. 3(2):185-198 (2008)journal articl
Perovskite Manganites Hosting Versatile Multiferroic Phases with Symmetric and Antisymmetric Exchange Strictions
Complete magnetoelectric (ME) phase diagrams of orthorhombic MnO
with and without magnetic moments on the ions have been established. Three
kinds of multiferroic ground states, the -cycloidal, the -cycloidal,
and the collinear -type phases, have been identified by the distinct ME
responses. The electric polarization of the -type phase dominated by the
symmetric spin exchange () is more than 10 times as
large as that of the -cycloidal phase dominated by the antisymmetric one
(), and the ME response is enhanced near the
bicritical phase boundary between these multiferroic phases of different
origins. These findings will provide an important clue for the development of
the magnetically induced multiferroics.Comment: 5 pages, 3 figure
Quality engineering of a traction alternator by robust design
Robust design is an engineering methodology for improving productivity during research and development so that high-quality products can be developed and produced quickly and at low cost. A large electrical company was developing traction alternators for a diesel electrical engine. Customer requirement was to obtain very high efficiency which, in turn, was influenced by several design parameters. The usual approach of the 'design-build-test' cycle was considered time-consuming and costly; it used to take anywhere from 4 months to 1 year before finalizing the product design parameters as it involved physical assembly and also testing. Instead, the authors used Taguchi's parameter design approach. This approach took about 8 weeks to arrive at optimum design parameter values; clearly demonstrating the cutting edge of this methodology over the traditional design-build-test approach. The prototype built and tested accordingly gave satisfactory overall performance, meeting and even exceeding customer requirements
Electromagnons in the multiferroic state of perovskite manganites with symmetric-exchange striction
We have investigated electrically-active magnetic excitations
(electromagnons) in perovskite manganites with the -type (up-up-down-down)
spin structure by terahertz spectroscopy. EuYMnO (0.11) and YLuMnO (01) without magnetic -moments,
which host collinear sinusoidal, -type, cycloidal, and -type spin orders,
are used to examine the systematics of possible electromagnons. Three-peak
structures (23, 35, 45 cm) of magnetic origin show up in the -type
phase with little composition () dependence of frequencies, making a
contrast with the electromagnons observed in the cycloidal-spin ()
phases. One of these electromagnon is ascribed to the zone-edge magnon mode
based on the calculated magnon dispersions.Comment: 5 pages, 4 figure
Electromagnons in the multiferroic state of perovskite manganites with symmetric-exchange striction
We have investigated electrically-active magnetic excitations
(electromagnons) in perovskite manganites with the -type (up-up-down-down)
spin structure by terahertz spectroscopy. EuYMnO (0.11) and YLuMnO (01) without magnetic -moments,
which host collinear sinusoidal, -type, cycloidal, and -type spin orders,
are used to examine the systematics of possible electromagnons. Three-peak
structures (23, 35, 45 cm) of magnetic origin show up in the -type
phase with little composition () dependence of frequencies, making a
contrast with the electromagnons observed in the cycloidal-spin ()
phases. One of these electromagnon is ascribed to the zone-edge magnon mode
based on the calculated magnon dispersions.Comment: 5 pages, 4 figure
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