148,716 research outputs found
The Cylindrical Antenna with Tapered Resistive Loading Scientific Report No. 5
Current, input impedance, and far field pattern of cylindrical antenna with tapered resistive loadin
Symmetry-preserving Loop Regularization and Renormalization of QFTs
A new symmetry-preserving loop regularization method proposed in \cite{ylw}
is further investigated. It is found that its prescription can be understood by
introducing a regulating distribution function to the proper-time formalism of
irreducible loop integrals. The method simulates in many interesting features
to the momentum cutoff, Pauli-Villars and dimensional regularization. The loop
regularization method is also simple and general for the practical calculations
to higher loop graphs and can be applied to both underlying and effective
quantum field theories including gauge, chiral, supersymmetric and
gravitational ones as the new method does not modify either the lagrangian
formalism or the space-time dimension of original theory. The appearance of
characteristic energy scale and sliding energy scale offers a
systematic way for studying the renormalization-group evolution of gauge
theories in the spirit of Wilson-Kadanoff and for exploring important effects
of higher dimensional interaction terms in the infrared regime.Comment: 13 pages, Revtex, extended modified version, more references adde
Phased models for evaluating the performability of computing systems
A phase-by-phase modelling technique is introduced to evaluate a fault tolerant system's ability to execute different sets of computational tasks during different phases of the control process. Intraphase processes are allowed to differ from phase to phase. The probabilities of interphase state transitions are specified by interphase transition matrices. Based on constraints imposed on the intraphase and interphase transition probabilities, various iterative solution methods are developed for calculating system performability
\u3cem\u3eDrosophila\u3c/em\u3e Vitelline Membrane Assembly: A Critical Role for an Evolutionarily Conserved Cysteine in the “VM domain” of sV23
The vitelline membrane (VM), the oocyte proximal layer of the Drosophila eggshell, contains four major proteins (VMPs) that possess a highly conserved “VM domain” which includes three precisely spaced, evolutionarily conserved, cysteines (CX7CX8C). Focusing on sV23, this study showed that the three cysteines are not functionally equivalent. While substitution mutations at the first (C123S) or third (C140S) cysteines were tolerated, females with a substitution at the second position (C131S) were sterile. Fractionation studies showed that sV23 incorporates into a large disulfide linked network well after its secretion ceases, suggesting that post-depositional mechanisms are in place to restrict disulfide bond formation until late oogenesis, when the oocyte no longer experiences large volume increases. Affinity chromatography utilizing histidine tagged sV23 alleles revealed small sV23 disulfide linked complexes during the early stages of eggshell formation that included other VMPs, namely sV17 and Vml. The early presence but late loss of these associations in an sV23 double cysteine mutant suggests that reorganization of disulfide bonds may underlie the regulated growth of disulfide linked networks in the vitelline membrane. Found within the context of a putative thioredoxin active site (CXXS) C131, the critical cysteine in sV23, may play an important enzymatic role in isomerizing intermolecular disulfide bonds during eggshell assembly
Two Higgs Bi-doublet Left-Right Model With Spontaneous P and CP Violation
A left-right symmetric model with two Higgs bi-doublet is shown to be a
consistent model for both spontaneous P and CP violation. The flavor changing
neutral currents can be suppressed by the mechanism of approximate global U(1)
family symmetry. We calculate the constraints from neural meson mass
difference and demonstrate that a right-handed gauge boson
contribution in box-diagrams with mass well below 1 TeV is allowed due to a
cancellation caused by a light charged Higgs boson with a mass range GeV. The contribution to can be suppressed from
appropriate choice of additional CP phases appearing in the right-handed
Cabbibo-Kobayashi-Maskawa matrix. The model is also found to be fully
consistent with mass difference , and the mixing-induced CP
violation quantity , which is usually difficult for the
model with only one Higgs bi-doublet. The new physics beyond the standard model
can be directly searched at the colliders LHC and ILC.Comment: 25 pages, 6 figures, typos corrected, 1 figure added, published
versio
Angular-dependent Magnetoresistance Oscillations in NaCoO Single Crystal
We report measurements of the c-axis angular-dependent magnetoresistance
(AMR) for a NaCoO single crystal, with a magnetic field of 10 T
rotating within Co-O planes. Below the metal-insulator transition temperature
induced by the charge ordering, the oscillation of the AMR is dominated by a
two-fold rotational symmetry. The amplitudes of the oscillation corresponding
to the four- and six-fold rotational symmetries are distinctive in low
temperatures, but they merge into the background simultaneously at about 25 K.
The six-fold oscillation originates naturally from the lattice symmetry. The
observation of the four-fold rotational symmetry is consistent with the picture
proposed by Choy, et al., that the Co lattice in the charge ordered state will
split into two orthorhombic sublattice with one occupied by Co ions and
the other by Co ions. We have also measured the c-axis AMR for
NaCoO and NaCoO single crystals, and found no
evidence for the existence of two- and four-fold symmetries.Comment: 4 pages, 6 figures. Submitted to PR
Visual Dynamics: Probabilistic Future Frame Synthesis via Cross Convolutional Networks
We study the problem of synthesizing a number of likely future frames from a
single input image. In contrast to traditional methods, which have tackled this
problem in a deterministic or non-parametric way, we propose a novel approach
that models future frames in a probabilistic manner. Our probabilistic model
makes it possible for us to sample and synthesize many possible future frames
from a single input image. Future frame synthesis is challenging, as it
involves low- and high-level image and motion understanding. We propose a novel
network structure, namely a Cross Convolutional Network to aid in synthesizing
future frames; this network structure encodes image and motion information as
feature maps and convolutional kernels, respectively. In experiments, our model
performs well on synthetic data, such as 2D shapes and animated game sprites,
as well as on real-wold videos. We also show that our model can be applied to
tasks such as visual analogy-making, and present an analysis of the learned
network representations.Comment: The first two authors contributed equally to this wor
A simple theory of dipole antennas
Simple and quantitatively accurate representation of current distribution in dipole antenna
Anisotropic Magnetoresistance in Charge-Ordering :Strong Spin-Charge Coupling and Spin Ordering
Angular-dependent in-plane magnetoresistance (AMR) for single crystal
with charge ordering is studied systematically.
The anisotropic magnetoresistance shows a twofold symmetry at high temperature
with rotating H in the Co-O plane, while a sixfold symmetry below a certain
temperature (). At , the symmetry of AMR changes from twofold
to fourfold with rotating magnetic field (H) in the plane consisting of the
current and c-axis. The variation of AMR symmetry with temperature arises from
the subtle changes of the spin structure. These results give a direct evidence
for the itinerant electrons directly coupled to the localized spins.Comment: 4 pages, 4 figure
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