5,185 research outputs found
Semi-classical behavior of P\"oschl-Teller coherent states
We present a construction of semi-classical states for P\"oschl-Teller
potentials based on a supersymmetric quantum mechanics approach. The parameters
of these "coherent" states are points in the classical phase space of these
systems. They minimize a special uncertainty relation. Like standard coherent
states they resolve the identity with a uniform measure. They permit to
establish the correspondence (quantization) between classical and quantum
quantities. Finally, their time evolution is localized on the classical phase
space trajectory.Comment: 7 pages, 2 figures, 1 animatio
Recommended from our members
Measuring the effect of customer relationship management (CRM) components on the non financial performance of commercial banks: Egypt case
This paper presents customer relationship management (CRM) components as applied on the Egyptian Commercial Banks, examined from the bankers' point of view. Then, it intends to measure their effect on the level of customer satisfaction and loyalty from the customersâ point of view as examples of the non financial performance measures. The paper is quantitative in nature and consists of two different structured questionnaires using convenience/quota sampling. The first involved 180 employees in order to measure CRM applicability, and the second involved 270 customers to measure the level of customer satisfaction and loyalty and their effect on the Egyptian Commercial Banks' financial performance The findings show that the selected banks apply CRM components but the level of application differs from one bank to another. The results showed a significant positive relationship between CRM and customer satisfaction in the Egyptian Commercial Banks, when applying them together and not separately. In addition, there is a strong positive effect between customer satisfaction and loyalty which was reflected on the Commercial Banks' financial performance. The findings confirm the importance of studying and implementing CRM to achieve customer loyalty and improve the Egyptian Commercial Banks financial performance. Banks wishing to improve their relationships with customers need to focus on the CRM components to develop relevant and effective marketing strategies and tactics. The paper measures the CRM as a multidimensional construct as applied on the Egyptian Commercial Banks and relate it to the achievement of the ultimate goal of retaining customers to gaining a sustainable competitive advantage and achieve more profits
Spectral tensor-train decomposition
The accurate approximation of high-dimensional functions is an essential task
in uncertainty quantification and many other fields. We propose a new function
approximation scheme based on a spectral extension of the tensor-train (TT)
decomposition. We first define a functional version of the TT decomposition and
analyze its properties. We obtain results on the convergence of the
decomposition, revealing links between the regularity of the function, the
dimension of the input space, and the TT ranks. We also show that the
regularity of the target function is preserved by the univariate functions
(i.e., the "cores") comprising the functional TT decomposition. This result
motivates an approximation scheme employing polynomial approximations of the
cores. For functions with appropriate regularity, the resulting
\textit{spectral tensor-train decomposition} combines the favorable
dimension-scaling of the TT decomposition with the spectral convergence rate of
polynomial approximations, yielding efficient and accurate surrogates for
high-dimensional functions. To construct these decompositions, we use the
sampling algorithm \texttt{TT-DMRG-cross} to obtain the TT decomposition of
tensors resulting from suitable discretizations of the target function. We
assess the performance of the method on a range of numerical examples: a
modifed set of Genz functions with dimension up to , and functions with
mixed Fourier modes or with local features. We observe significant improvements
in performance over an anisotropic adaptive Smolyak approach. The method is
also used to approximate the solution of an elliptic PDE with random input
data. The open source software and examples presented in this work are
available online.Comment: 33 pages, 19 figure
A Survey on Retrieval of Mathematical Knowledge
We present a short survey of the literature on indexing and retrieval of
mathematical knowledge, with pointers to 72 papers and tentative taxonomies of
both retrieval problems and recurring techniques.Comment: CICM 2015, 20 page
New SUSYQM coherent states for Poschl-Teller potentials: a detailed mathematical analysis
In a recent short note [Bergeron H, Gazeau J P, Siegl P and Youssef A 2010
EPL 92 60003], we have presented the nice properties of a new family of
semi-classical states for P\"oschl-Teller potentials. These states are built
from a supersymmetric quantum mechanics approach and the parameters of these
"coherent" states are points in the classical phase space. In this article we
develop all the mathematical aspects that have been left apart in the previous
article (proof of the resolution of unity, detailed calculations of quantized
version of classical observables and mathematical study of the resulting
operators: problems of domains, self- adjointness or self-adjoint extensions).
Some additional questions as asymptotic behavior are also studied. Moreover,
the framework is extended to a larger class of P\"oschl-Teller potentials
Immunoregulatory soluble CTLA-4 modifies effector T cell responses in systemic lupus erythematosus
Acknowledgments This work was supported by Arthritis Research UK (Grant no. 19282). We are grateful to Dr. Nick Fluck for his invaluable support in recruiting patients for the study, and Mrs. Vivien Vaughan for her invaluable expertise in recruiting study participants and maintaining ethical documentation.Peer reviewedPublisher PD
An FFT method for the numerical differentiation
We consider the numerical differentiation of a function tabulated at equidistant points. The proposed method is based on the Fast Fourier Transform (FFT) and the singular value expansion of a proper Volterra integral operator that reformulates the derivative operator. We provide the convergence analysis of the proposed method and the results of a numerical experiment conducted for comparing the proposed method performance with that of the Neville Algorithm implemented in the NAG library
Thermal simulation of magnetization reversals for size-distributed assemblies of core-shell exchange biased nanoparticles
A temperature dependent coherent magnetization reversal model is proposed for
size-distributed assemblies of ferromagnetic nanoparticles and
ferromagnetic-antiferromagnetic core-shell nanoparticles. The nanoparticles are
assumed to be of uniaxial anisotropy and all aligned along their easy axis. The
thermal dependence is included by considering thermal fluctuations, implemented
via the N\'eel-Arrhenius theory. Thermal and angular dependence of
magnetization reversal loops, coercive field and exchange-bias field are
obtained, showing that F-AF size-distributed exchange-coupled nanoparticles
exhibit temperature-dependent asymmetric magnetization reversal. Also,
non-monotonic evolutions of He and Hc with T are demonstrated. The angular
dependence of Hc with T exhibits a complex behavior, with the presence of an
apex, whose position and amplitude are strongly T dependent. The angular
dependence of He with T exhibits complex behaviors, which depends on the AF
anisotropy and exchange coupling. The resulting angular behavior demonstrates
the key role of the size distribution and temperature in the magnetic response
of nanoparticles.Comment: Revised arguments in Introduction and last sectio
- âŠ