1,278 research outputs found
The distribution of localization centers in some discrete random systems
As a supplement of our previous work, we consider the localized region of the
random Schroedinger operators on and study the point process
composed of their eigenvalues and corresponding localization centers. For the
Anderson model, we show that, this point process in the natural scaling limit
converges in distribution to the Poisson process on the product space of energy
and space. In other models with suitable Wegner-type bounds, we can at least
show that any limiting point processes are infinitely divisible
The Current State of the Pediatric Emergency Medicine Workforce and Innovations to Improve Pediatric Care
Many hospitals and emergency departments lack resources to optimally care for ill and injured children, perpetuating risks of receiving fragmented and “uneven” care. In this article, we describe the present state of our pediatric emergency medicine workforce as well as the impact that different innovations could have on the future of pediatric emergency care. Many innovative initiatives, including physician and advanced practice provider education and training, pediatric readiness recognition programs, telemedicine and in-situ simulation outreach, and community paramedicine are being utilized to help bridge access gaps and augment the reach of the pediatric emergency medicine workforce. Advocacy for reimbursement for novel care delivery models, such as community paramedicine and telemedicine, and funding for outreach education programming is essential. Also, better understanding of our current training models for and utilization of advanced practice practitioners in pediatric emergency medicine is crucial to understanding the diversity of workforce growth and opportunity
Existence of the Bogoliubov S(g) operator for the quantum field theory
We prove the existence of the Bogoliubov S(g) operator for the
quantum field theory for coupling functions of compact support in space and
time. The construction is nonperturbative and relies on a theorem of
Kisy\'nski. It implies almost automatically the properties of unitarity and
causality for disjoint supports in the time variable.Comment: LaTeX, 24 pages, minor modifications, typos correcte
Influence of Micro-Cantilever Geometry and Gap on Pull-in Voltage
In this paper, we study the behaviour of a microcantilever beam under
electrostatic actuation using finite difference method. This problem has a lot
of applications in MEMS based devices like accelerometers, switches and others.
In this paper, we formulated the problem of a cantilever beam with proof mass
at its end and carried out the finite difference solution. we studied the
effects of length, width, and the gap size on the pull-in voltage using data
that are available in the literature. Also, the stability limit is compared
with the single degree of freedom commonly used in the earlier literature as an
approximation to calculate the pull-in voltage.Comment: Submitted on behalf of TIMA Editions
(http://irevues.inist.fr/tima-editions
Natural convection heat transfer in nanofluids - a numerical study
Natural convection heat transfer in nanofluids has been investigated numerically using computational fluid dynamics (CFD) approach. Analytical models that describe molecular viscosity, density, specific heat, thermal conductivity and coefficient of thermal expansion have been considered in terms of volume fraction and size of nanoparticles, size of base fluid molecule and temperature. The uniform suspensions of different concentrations of Al2O3 in base fluid (water) are considered as nanofluids. Thermal conductivity of the nanofluids has been obtained by solving the governing equations in conjunction with Kinetic model and interfacial layer model using FLUNET 6.3. Numerical simulations have been carried out in a closed pipe for L/D = 1.0. The numerical values of k have also been compared with the experimental values available in the literature. Both the models gave similar predictions with experimentally compared values of k
Investigating corrosion effects and heat transfer enhancement in smaller size radiators using CNT-nanofluids
Nanofluids have been extensively studied in the past to enhance the heat transfer performance and efficiency of systems. However, corrosion effects have been paid very little attention and thus this work presents an experimental study on the effect of carbon nanotubes (CNT) on corrosion of three different metals under study such as aluminium alloy, stainless steel and copper, respectively. The work was further extended to study the heat transfer performance in a car radiator of two different sizes. Both the studies were performed using four different fluids such as water, ethylene glycol, 0.02 % CNT-nanofluid and 0.1 % CNT-nanofluid, respectively. It was observed that among the three metals, the highest rate of corrosion occurs to aluminium, followed by stainless steel and copper, irrespective of the fluid used. The rate of corrosion increased with the increase in temperature (27–90 °C) in all cases. The experimental results showed that the stable CNT-nanofluids prepared in this work showed better heat transfer performance in both engines. Moreover, the smaller radiator using the CNT-nanofluids depicted enhanced heat transfer rates compared to the standard radiator using water and ethylene glycol
Renormalized energy concentration in random matrices
We define a "renormalized energy" as an explicit functional on arbitrary
point configurations of constant average density in the plane and on the real
line. The definition is inspired by ideas of [SS1,SS3]. Roughly speaking, it is
obtained by subtracting two leading terms from the Coulomb potential on a
growing number of charges. The functional is expected to be a good measure of
disorder of a configuration of points. We give certain formulas for its
expectation for general stationary random point processes. For the random
matrix -sine processes on the real line (beta=1,2,4), and Ginibre point
process and zeros of Gaussian analytic functions process in the plane, we
compute the expectation explicitly. Moreover, we prove that for these processes
the variance of the renormalized energy vanishes, which shows concentration
near the expected value. We also prove that the beta=2 sine process minimizes
the renormalized energy in the class of determinantal point processes with
translation invariant correlation kernels.Comment: last version, to appear in Communications in Mathematical Physic
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