6,711 research outputs found
A Novel Stealthy Target Detection Based on Stratospheric Balloon-borne Positional Instability due to Random Wind
A novel detection for stealthy target model F-117A with a higher aspect vision is introduced by using Stratospheric Balloon-borne Bistatic system. The potential problem of proposed scheme is platform instability impacted on the balloon by external wind force. The flight control system is studied in detail under typical random process, which is defined by Dryden turbulence spectrum. To accurately detect the stealthy target model, a real Radar Cross Section (RCS) based on physical optics (PO) formulation is applied. The sensitivity of the proposed scheme has been improved due to increasing PO – scattering field of stealthy model with higher aspect angle comparing to the conventional ground -based system. Simulations demonstrate that the proposed scheme gives much higher location accuracy and reduces location errors
Polarized Deep Inelastic Scattering Off the "Neutron" From Gauge/String Duality
We investigate deep inelastic scattering off the polarized "neutron" using
gauge/string duality. The "neutron" corresponds to a supergravity mode of the
neutral dilatino. Through introducing the Pauli interaction term into the
action in space, we calculate the polarized deep inelastic
structure functions of the "neutron" in supergravity approximation at large t'
Hooft coupling and finite with . In
comparison with the charged dilatino "proton," which has been obtained in the
previous work by Gao and Xiao, we find the structure functions of the "neutron"
are power suppressed at the same order as the ones of the "proton." Especially,
we find the Burkhardt-Cottingham-like sum rule, which is satisfied in the work
by Gao and Xiao, is broken due to the Pauli interaction term. We also
illustrate how such a Pauli interaction term can arise naturally from higher
dimensional fermion-graviton coupling through the usual Kaluza-Klein reduction.Comment: 21pages,5figures, published versio
Design of Compact BPF and Planar Diplexer for UMTS using Embedded-scheme Resonator
A compact planar diplexer utilizing embedded-scheme resonator (ESR) is designed for universal mobile telecommunications system (UMTS). The ESR is formed by embedding interdigital resonators into an open loop resonator. Based on the proposed ESR, a narrowband bandpass filter suitable for diplexer design is proposed, fabricated and measured. The measured results demonstrate that the filter exhibits good transmission properties within band and high frequency selectivity. The rectangular area occupied by the filter has overall dimensions only 0.086λg by 0.105λg, promises good potential in wireless communication systems that require compact size and high encapsulation quality. Then, a compact planar diplexer operating at the TX-band of 1920-1980MHz and the RX-band of 2110-2170MHz, which is composed of a meander T-junction and two filters initially separately designed, is synthesized, simulated and measured. Both the simulated and measured results indicate that satisfied impedance matching and good isolation between two paths have been achieved
Lepton flavor violating signals of the neutral top-pion in future lepton colliders
The presence of the top-pions in the low-energy spectrum is
an inevitable feature of the topcolor scenario. Taking into account the
constraints of the present experimental limit of the lepton flavor
violating() process on the free parameters of
topcolor-assisted techicolor(TC2) models, we study the contributions of the
neutral top-pion to the processes (or ), (or ), , and via the
flavor changing () couplings and discuss the
possibility of searching for the signals via these processes in future
lepton colliders.Comment: References added, some typos corrected. Version to be published in
Phys. Rev.
Compact and High Performance Dual-band Bandpass Filter Using Resonator-embedded Scheme for WLANs
A compact microstrip dual-band bandpass filter (DBBPF) with high selectivity and good suppression for wireless local area networks (WLANs) is proposed utilizing a novel embedded scheme resonator. Two passbands are produced by a pair of embedded half-wavelength meandered stepped-impedance resonator (MSIR) and a quadwavelength short stub loaded stepped-impedance resonator (SIR) separately. The resonator is fed by folded Tshaped capacitive source-load coupling microstrip feed line, and four transmission zeros are obtained at both sides of the bands to improve selectivity and suppression. Simultaneously, the size of the filter is extermely compact because embedding half-wavelength MSIR only changes the interior configuration of quad-wavelength SIR. To validate the design method, the designed filter is fabricated and measured. Both simulated and measured results indicate that good transmission property has been achieved
Variational calculations on the hydrogen molecular ion
We present high-precision non-relativistic variational calculations of bound
vibrational-rotational state energies for the and molecular
ions in each of the lowest electronic states of , , and
symmetry. The calculations are carried out including coupling between
and states but without using the Born-Oppenheimer or any
adiabatic approximation. Convergence studies are presented which indicate that
the resulting energies for low-lying levels are accurate to about .
Our procedure accounts naturally for the lambda-doubling of the state.Comment: 23 pp., RevTeX, epsf.sty, 5 figs. Enhanced data in Table II, dropped
3 figs. from previous versio
Entanglement distribution maximization over one-side Gaussian noisy channel
The optimization of entanglement evolution for two-mode Gaussian pure states
under one-side Gaussian map is studied. Even there isn't complete information
about the one-side Gaussian noisy channel, one can still maximize the
entanglement distribution by testing the channel with only two specific states
The Equation of State and Quark Number Susceptibility in Hard-Dense-Loop Approximation
Based on the method proposed in [ H. S. Zong, W. M. Sun, Phys. Rev. \textbf{D
78}, 054001 (2008)], we calculate the equation of state (EOS) of QCD at zero
temperature and finite quark chemical potential under the hard-dense-loop (HDL)
approximation. A comparison between the EOS under HDL approximation and the
cold, perturbative EOS of QCD proposed by Fraga, Pisarski and Schaffner-Bielich
is made. It is found that the pressure under HDL approximation is generally
smaller than the perturbative result. In addition, we also calculate the quark
number susceptibility (QNS) at finite temperature and finite chemical potential
under hard-thermal/dense-loop (HTL/HDL) approximation and compare our results
with the corresponding ones in the previous literature.Comment: 12 pages, 3 figure
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