145,125 research outputs found
Low Power Reversible Parallel Binary Adder/Subtractor
In recent years, Reversible Logic is becoming more and more prominent
technology having its applications in Low Power CMOS, Quantum Computing,
Nanotechnology, and Optical Computing. Reversibility plays an important role
when energy efficient computations are considered. In this paper, Reversible
eight-bit Parallel Binary Adder/Subtractor with Design I, Design II and Design
III are proposed. In all the three design approaches, the full Adder and
Subtractors are realized in a single unit as compared to only full Subtractor
in the existing design. The performance analysis is verified using number
reversible gates, Garbage input/outputs and Quantum Cost. It is observed that
Reversible eight-bit Parallel Binary Adder/Subtractor with Design III is
efficient compared to Design I, Design II and existing design.Comment: 12 pages,VLSICS Journa
Some Superstring Amplitude Computations with the Non-Minimal Pure Spinor Formalism
We use the non-minimal pure spinor formalism to compute in a super-Poincare
covariant manner the four-point massless one and two-loop open superstring
amplitudes, and the gauge anomaly of the six-point one-loop amplitude. All of
these amplitudes are expressed as integrals of ten-dimensional superfields in a
"pure spinor superspace" which involves five coordinates covariantly
contracted with three pure spinors. The bosonic contribution to these
amplitudes agrees with the standard results, and we demonstrate identities
which show how the and tensors naturally emerge from
integrals over pure spinor superspace.Comment: 20 pages, harvmac te
- and -wave components induced around a vortex in -wave superconductors
Vortex structure of -wave superconductors is microscopically
analyzed in the framework of the quasi-classical Eilenberger equations. If the
pairing interaction contains an -wave (-wave) component in addition
to a -wave component, the -wave (-wave) component of
the order parameter is necessarily induced around a vortex in
-wave superconductors. The spatial distribution of the induced
-wave and -wave components is calculated. The -wave component has
opposite winding number around vortex near the -vortex core and
its amplitude has the shape of a four-lobe clover. The amplitude of
-component has the shape of an octofoil. These are consistent with
results based on the GL theory.Comment: RevTex,9 pages, 6 figures in a uuencoded fil
Coulomb correlation effects in zinc monochalcogenides
Electronic structure and band characteristics for zinc monochalcogenides with
zinc-blende- and wurtzite-type structures are studied by first-principles
density-functional-theory calculations with different approximations. It is
shown that the local-density approximation underestimates the band gap and
energy splitting between the states at the top of the valence band, misplaces
the energy levels of the Zn-3d states, and overestimates the
crystal-field-splitting energy. Regardless of the structure type considered,
the spin-orbit-coupling energy is found to be overestimated for ZnO and
underestimated for ZnS with wurtzite-type structure, and more or less correct
for ZnSe and ZnTe with zinc-blende-type structure. The order of the states at
the top of the valence band is found to be anomalous for ZnO in both
zinc-blende- and wurtzite-type structure, but is normal for the other zinc
monochalcogenides considered. It is shown that the Zn-3d electrons and their
interference with the O-2p electrons are responsible for the anomalous order.
The typical errors in the calculated band gaps and related parameters for ZnO
originate from strong Coulomb correlations, which are found to be highly
significant for this compound. The LDA+U approach is by and large found to
correct the strong correlation of the Zn-3d electrons, and thus to improve the
agreement with the experimentally established location of the Zn-3d levels
compared with that derived from pure LDA calculations
Use of extended and prepared reference objects in experimental Fourier transform X-ray holography
The use of one or more gold nanoballs as reference objects for Fourier
Transform holography (FTH) is analysed using experimental soft X-ray
diffraction from objects consisting of separated clusters of these balls. The
holograms are deconvoluted against ball reference objects to invert to images,
in combination with a Wiener filter to control noise. A resolution of ~30nm,
smaller than one ball, is obtained even if a large cluster of balls is used as
the reference, giving the best resolution yet obtained by X-ray FTH. Methods of
dealing with missing data due to a beamstop are discussed. Practical prepared
objects which satisfy the FTH condition are suggested, and methods of forming
them described.Comment: 7 pages, 2 figures, submitted to Applied Physics Letter
First Order Kaon Condensate
First order Bose condensation in asymmetric nuclear matter and in neutron
stars is studied, with particular reference to kaon condensation. We
demonstrate explicitly why the Maxwell construction fails to assure equilibrium
in multicomponent substances. Gibbs conditions and conservation laws require
that for phase equilibrium, the charge density must have opposite sign in the
two phases of isospin asymmetric nuclear matter. The mixed phase will therefore
form a Coulomb lattice with the rare phase occupying lattice sites in the
dominant phase. Moreover, the kaon condensed phase differs from the normal
phase, not by the mere presence of kaons in the first, but also by a difference
in the nucleon effective masses. The mixed phase region, which occupies a large
radial extent amounting to some kilometers in our model neutron stars, is thus
highly heterogeneous. It should be particularly interesting in connection with
the pulsar glitch phenomenon as well as transport properties.Comment: 25 pagees, 20 figures, Late
Further observations of space shuttle plasma‐electrodynamic effects from OSS‐1/STS‐3
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95259/1/grl3101.pd
Status of longtail tuna, Thunnus tonggol fishery along the Northwest coast of India
Longtail tuna, Thunnus tonggol, is a neritic species with continuous
distribution along the continent of Asia from Iran to mainland China (Yesaki,
1993). The average landings during the 1995-2002 period along the Indian coast
was about 5970 t of which 78% was contributed from the North-west region.
Although the species has so far been reported to be exploited marginally only,
since 1998 there has been a perceptible intensification of fishing activities mainly
due to technological advancements all along the Indian coast and especially so
along the North-west coast (Anon., 1996). Catches of T. tonggol which has
shown an increasing trend along the North-west coast since the early 90s peaked
during 2000 and subsequently showed a sudden decline with catches as low as
when the fishery was just developing during 1990-92 period
Finite temperature formalism for nonabelian gauge theories in the physical phase space
We establish a new framework of finite temperature field theory for
Yang-Mills theories in the physical phase space eliminating all unphysical
degrees of freedoms. Relating our method to the imaginary time formalism of
James and Landshoff in temporal axial gauge, we calculate the two-loop pressure
and provide a systematic and unique method to construct the additional vertices
encountered in their approach.Comment: 18 pages, 5 postscript figures, uses revtex, eps
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