5 research outputs found
Analysis of a General Family of Regularized Navier-Stokes and MHD Models
We consider a general family of regularized Navier-Stokes and
Magnetohydrodynamics (MHD) models on n-dimensional smooth compact Riemannian
manifolds with or without boundary, with n greater than or equal to 2. This
family captures most of the specific regularized models that have been proposed
and analyzed in the literature, including the Navier-Stokes equations, the
Navier-Stokes-alpha model, the Leray-alpha model, the Modified Leray-alpha
model, the Simplified Bardina model, the Navier-Stokes-Voight model, the
Navier-Stokes-alpha-like models, and certain MHD models, in addition to
representing a larger 3-parameter family of models not previously analyzed. We
give a unified analysis of the entire three-parameter family using only
abstract mapping properties of the principle dissipation and smoothing
operators, and then use specific parameterizations to obtain the sharpest
results. We first establish existence and regularity results, and under
appropriate assumptions show uniqueness and stability. We then establish
results for singular perturbations, including the inviscid and alpha limits.
Next we show existence of a global attractor for the general model, and give
estimates for its dimension. We finish by establishing some results on
determining operators for subfamilies of dissipative and non-dissipative
models. In addition to establishing a number of results for all models in this
general family, the framework recovers most of the previous results on
existence, regularity, uniqueness, stability, attractor existence and
dimension, and determining operators for well-known members of this family.Comment: 37 pages; references added, minor typos corrected, minor changes to
revise for publicatio
Comparative analysis of mathematical modeling methods of information and telecommunication networks of critical applying
В статье проведен сравнительный анализ методов математического моделирования информационнотелекоммуникационных сетей систем критического применения. Рассмотрены методы аналитического моделирования, гибридного моделирования, а также предложены методы расчета однородных замкнутых сетей систем массового обслуживания (СеМО) общего вида.У статті наведений аналіз інформаційно-телекомунікаційних мереж систем критичного застосування, розглянуті методи аналітичного моделювання, метод гібридного моделювання, а також методи розрахунку однорідних замкнутих мереж системмасового обслуговування (МeMO) загального вигляду.In this article was conducted comparative analysis of mathematical modeling methods of information and telecommunication networks of critical applying, considered methods of analytical modeling, hybrid modeling method as well as methods for calculating homogeneous closed general form
Traffic adjustment in information and telecommunication networks of critical applying
В статье проведены расчеты параметров QoS, рассмотрены существующие методы обслуживания, проведен анализ необходимого размера входных буферов в устройствах АТМ сетей.У статті проведені розрахунки параметрів QOS, розглянуті існуючі методи обслуговування, проведений аналіз необхідного розміру вхідних буферів в пристроях АТМ мереж.The calculations of QoS parameters has been conducted in this article. Also it was observed existing of service methods and necessary capacity of incoming buffer in devices of ATM networks were analyzed