Spectral theory approach for a class of radial indefinite variational problems

This paper considers an infinite-buffer queuing system with birth-death modulated Markovian arrival process (BDMMAP) with arbitrary service time distribution. BDMMAP is an excellent representation of the arrival process, where the fractal behavior such as burstiness, correlation, and self-similarity is observed, for example, in ethernet LAN traffic systems. This model was first apprised by Nishimura (2003), and to analyze it, he proposed a twofold spectral theory approach. It seems from the investigations that Nishimura’s approach is tedious and difficult to employ for practical purposes. The objective of this paper is to analyze the same model with an alternative methodology proposed by Chaudhry et al. (2013) (to be referred to as CGG method). The CGG method appears to be rather simple, mathematically tractable, and easy to implement as compared to Nishimura’s approach. The Achilles tendon of the CGG method is the roots of the characteristic equation associated with the probability generating function (pgf) of the queue length distribution, which absolves any eigenvalue algebra and iterative analysis. Both the methods are presented in stepwise manner for easy accessibility, followed by some illustrative examples in accordance with the context.

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A spectral theory approach for extreme value analysis in a tandem of fluid queues

Queueing Systems ◽

10.1007/s11134-014-9395-9 ◽

2014 ◽

Vol 78 (2) ◽

pp. 121-154 ◽

Cited By ~ 3

Author(s):

J. W. Bosman ◽

R. Núñez-Queija

Keyword(s):

Spectral Theory ◽

Extreme Value ◽

Extreme Value Analysis ◽

Theory Approach ◽

Value Analysis ◽

Fluid Queues

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Temperature and velocity relaxation in plasma. Spectral theory approach

Journal of Physics and Electronics ◽

10.15421/331919 ◽

2019 ◽

Vol 27 (2) ◽

pp. 29-36 ◽

Cited By ~ 1

Author(s):

S. A. Sokolovsky ◽

A. I. Sokolovsky ◽

І. S. Kravchuk ◽

O. A. Grinishin

Keyword(s):

Integral Operator ◽

Spectral Theory ◽

Landau Equation ◽

Collision Integral ◽

Relaxation Processes ◽

Nonequilibrium Systems ◽

Theory Approach ◽

Relaxation Coefficients ◽

Bogolyubov Method ◽

Functional Hypothesis

The electron temperature and velocity relaxation of completely ionized plasma is studied on the basis of kinetic equation obtained from the Landau equation in a generalized Lorentz model. In this model contrary to the standard one ions form an equilibrium subsystem. Relaxation processes in the system are studied on the basis of spectral theory of the collision integral operator. This leads to an exact theory of relaxation processes of component temperatures and velocities equalizing. The relation of the developed theory with the Bogolyubov method of the reduced description of nonequilibrium systems is established, because the theory contains a proof of the relevant functional hypothesis, the idea of which is the basis of the Bogolyubov method. The temperature and velocity relaxation coefficients as eigenvalues of the collision integral operator are calculated by the method of truncated expansion of its eigenfunctions in the Sonine orthogonal polynomials. The coefficients are found in one- and two-polynomial approximation. As one can expect, convergence of this expansion is slow.

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Analysis of priority channel assignment schemes in mobile cellular communication systems: a spectral theory approach

Performance Evaluation ◽

10.1016/j.peva.2004.07.001 ◽

2005 ◽

Vol 59 (2-3) ◽

pp. 199-224 ◽

Cited By ~ 8

Author(s):

Vicent Pla ◽

Vicente Casares-Giner

Keyword(s):

Spectral Theory ◽

Channel Assignment ◽

Communication Systems ◽

Cellular Communication ◽

Theory Approach ◽

Mobile Cellular ◽

Cellular Communication Systems

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Ab initio band theory approach to electron energy loss near edge structures

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100104595 ◽

1988 ◽

Vol 46 ◽

pp. 506-507

Author(s):

Xudong Weng ◽

O.F. Sankey ◽

Peter Rez

Keyword(s):

Ab Initio ◽

Local Density ◽

Interpolation Method ◽

Atomic Orbital ◽

Plane Waves ◽

Large Set ◽

Theory Approach ◽

Band Theory ◽

Atomic Orbitals ◽

Pseudopotential Calculations

Single electron band structure techniques have been applied successfully to the interpretation of the near edge structures of metals and other materials. Among various band theories, the linear combination of atomic orbital (LCAO) method is especially simple and interpretable. The commonly used empirical LCAO method is mainly an interpolation method, where the energies and wave functions of atomic orbitals are adjusted in order to fit experimental or more accurately determined electron states. To achieve better accuracy, the size of calculation has to be expanded, for example, to include excited states and more-distant-neighboring atoms. This tends to sacrifice the simplicity and interpretability of the method.In this paper. we adopt an ab initio scheme which incorporates the conceptual advantage of the LCAO method with the accuracy of ab initio pseudopotential calculations. The so called pscudo-atomic-orbitals (PAO's), computed from a free atom within the local-density approximation and the pseudopotential approximation, are used as the basis of expansion, replacing the usually very large set of plane waves in the conventional pseudopotential method. These PAO's however, do not consist of a rigorously complete set of orthonormal states.

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Perceptions of a Collaborative Professional Learning Program: Seeing the “Bigger Picture”

Perspectives of the ASHA Special Interest Groups ◽

10.1044/2019_persp-19-00041 ◽

2020 ◽

Vol 5 (1) ◽

pp. 290-303

Author(s):

P. Charlie Buckley ◽

Kimberly A. Murza ◽

Tami Cassel

Keyword(s):

Data Analysis ◽

Professional Learning ◽

Social Communication ◽

Special Educators ◽

Service Providers ◽

Integrative Approach ◽

Theory Approach ◽

Learning Program ◽

Speech Language Pathologists ◽

Related Service

Purpose The purpose of this study was to explore the perceptions of special education practitioners (i.e., speech-language pathologists, special educators, para-educators, and other related service providers) on their role as communication partners after participation in the Social Communication and Engagement Triad (Buckley et al., 2015 ) yearlong professional learning program. Method A qualitative approach using interviews and purposeful sampling was used. A total of 22 participants who completed participation in either Year 1 or Year 2 of the program were interviewed. Participants were speech-language pathologists, special educators, para-educators, and other related service providers. Using a grounded theory approach (Glaser & Strauss, 1967 ) to data analysis, open, axial, and selective coding procedures were followed. Results Three themes emerged from the data analysis and included engagement as the goal, role as a communication partner, and importance of collaboration. Conclusions Findings supported the notion that educators see the value of an integrative approach to service delivery, supporting students' social communication and engagement across the school day but also recognizing the challenges they face in making this a reality.

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