2,463 research outputs found
Lifshitz Scaling Effects on Holographic Superconductors
Via numerical and analytical methods, the effects of the Lifshitz dynamical
exponent on holographic superconductors are studied in some detail,
including wave and wave models. Working in the probe limit, we find
that the behaviors of holographic models indeed depend on concrete value of
. We obtain the condensation and conductivity in both Lifshitz black hole
and soliton backgrounds with general . For both wave and wave models
in the black hole backgrounds, as increases, the phase transition becomes
more difficult and the growth of conductivity is suppressed. For the Lifshitz
soliton backgrounds, when increases (), the critical chemical
potential decreases in the wave cases but increases in the wave cases.
For wave models in both Lifshitz black hole and soliton backgrounds, the
anisotropy between the AC conductivity in different spatial directions is
suppressed when increases. The analytical results uphold the numerical
results.Comment: Typos corrected; Footnote added; References added; To be published in
Nuclear Physics
Cherry Creek North Improvements and Fillmore Plaza Landscape Performance Benefits Assessment
The 16-block Cherry Creek North retail district was designed to be Denver\u27s premier outdoor shopping area. Yet deteriorating infrastructure, tired aesthetics and competition from an adjacent indoor mall had led to steady decline. Fillmore Plaza in the heart of the district was no longer a desirable public space since being closed to vehicular traffic in 1987. The new streetscape strengthens the retail environment, preserves the district\u27s history and character, improves identity, beautifies the area, provides new lighting, improves signage, and adds 20 Art and Garden Places for shoppers to relax and linger. The redesigned Fillmore Plaza is now a vibrant hybrid street closed off to traffic only during planned pedestrian events
Five-dimensional generalized gravity with curvature-matter coupling
The generalized gravity with curvature-matter coupling in
five-dimensional (5D) spacetime can be established by assuming a
hypersurface-orthogonal spacelike Killing vector field of 5D spacetime, and it
can be reduced to the 4D formulism of FRW universe. This theory is quite
general and can give the corresponding results to the Einstein gravity,
gravity with both no-coupling and non-minimal coupling in 5D spacetime as
special cases, that is, we would give the some new results besides previous
ones given by Ref.\cite{60}. Furthermore, in order to get some insight into the
effects of this theory on the 4D spacetime, by considering a specific type of
models with and , we not
only discuss the constraints on the model parameters , , but also
illustrate the evolutionary trajectories of the scale factor , the
deceleration parameter and the scalar field , in
the reduced 4D spacetime. The research results show that this type of
gravity models given by us could explain the current accelerated expansion of
our universe without introducing dark energy.Comment: arXiv admin note: text overlap with arXiv:0912.4581,
arXiv:gr-qc/0411066 by other author
Direct numerical simulation of compressible interfacial multiphase flows using a mass-momentum-energy consistent volume-of-fluid method
Compressible interfacial multiphase flows (CIMF) are essential to different
applications, such as liquid fuel injection in supersonic propulsion systems.
Since high-level details in CIMF are often difficult to measure in experiments,
numerical simulation is an important alternative to shed light on the unclear
physics. A direct numerical simulation (DNS) of CIMF will need to rigorously
resolve the shock waves, the interfaces, and the interaction between the two. A
novel numerical method has been developed and implemented in the present study.
The geometric volume-of-fluid (VOF) method is employed to resolve the sharp
interfaces between the two phases. The advection of the density, momentum, and
energy is carried out consistently with VOF advection. To suppress spurious
oscillations near shocks, numerical diffusion is introduced based on the
Kurganov-Tadmor method in the region away from the interface. The contribution
of pressure is incorporated using the projection method and the pressure is
obtained by solving the Poisson-Helmholtz equation, which allows the present
method to handle flows with all Mach numbers. The present method is tested by a
sequence of CIMF problems. The simulation results are validated against
theories, experiments, and other simulations, and excellent agreement has been
achieved. In particular, the linear single-mode Richtmyer-Meshkov instabilities
with finite Weber and Reynolds numbers are simulated. The simulation results
agree very well with the linear stability theory, which affirms the capability
of the present method in capturing the viscous and capillary effects on
shock-interface interaction
Park Avenue & US 50 Redevelopment Streetscape Performance Benefits Assessment
The town of South Lake Tahoe experienced undisciplined development, which created traffic congestion, limited connectivity to recreational assets, and negatively impacted the scenic and environmental quality of Lake Tahoe and the region. In response, strict environmental regulations were developed, which subsequently ceased development activities. Faced with serious environmental and economic problems, residents, officials, and developers jointly revised development regulations and worked to strategically deploy development monies to give the town a new future. Today, the town\u27s Park Avenue Corridor with its wide sidewalks, interconnected plazas, consistent architecture, gondola, intermodal transit center, street furniture, and integrated stormwater management is a national model for redevelopment that promotes economic vitality, improves the natural environment, and creates a strong sense of place
Next-to-leading order QCD corrections to associated production via the flavor-changing neutral-current couplings at hadron colliders
We present the complete next-to-leading order (NLO) QCD corrections to
associated production induced by the model-independent and
flavor-changing neutral-current couplings at hadron colliders, respectively.
Our results show that, for the coupling the NLO QCD corrections can
enhance the total cross sections by about 60% and 42%, and for the
coupling by about 51% and 43% at the Tevatron and LHC, respectively. The NLO
corrections, for the couplings, can enhance the total cross sections by
about 27%, and by about 42% for the coupling at the LHC. We also consider
the mixing effects between the and couplings for this process,
which can either be large or small depending on the values of the anomalous
couplings. Besides, the NLO corrections reduce the dependence of the total
cross sections on the renormalization or factorization scale significantly,
which lead to increased confidence on the theoretical predictions. And we also
evaluate the NLO corrections to several important kinematic distributions.Comment: Published version in Phys. Rev.
Detect-and-forward relaying aided cooperative spatial modulation for wireless networks
A novel detect-and-forward (DeF) relaying aided cooperative SM scheme is proposed, which is capable of striking a flexible tradeoff in terms of the achievable bit error ratio (BER), complexity and unequal error protection (UEP). More specifically, SM is invoked at the source node (SN) and the information bit stream is divided into two different sets: the antenna index-bits (AI-bits) as well as the amplitude and phase modulation-bits (APM-bits). By exploiting the different importance of the AI-bits and the APM-bits in SM detection, we propose three low-complexity, yet powerful relay protocols, namely the partial, the hybrid and the hierarchical modulation (HM) based DeF relaying schemes. These schemes determine the most appropriate number of bits to be re-modulated by carefully considering their potential benefits and then assigning a specific modulation scheme for relaying the message. As a further benefit, the employment of multiple radio frequency (RF) chains and the requirement of tight inter-relay synchronization (IRS) can be avoided. Moreover, by exploiting the benefits of our low-complexity relaying protocols and our inter-element interference (IEI) model, a low-complexity maximum-likelihood (ML) detector is proposed for jointly detecting the signal received both via the source-destination (SD) and relay-destination (RD) links. Additionally, an upper bound of the BER is derived for our DeF-SM scheme. Our numerical results show that the bound is asymptotically tight in the high-SNR region and the proposed schemes provide beneficial system performance improvements compared to the conventional MIMO schemes in an identical cooperative scenario.<br/
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