The dynamics of short envelope solitons in media with controlled dispersion
Propagation of the short vector envelope solitons in a inhomogeneous medium with linear potential in coupled third–order nonlinear Shrodinger equations frame is considered. Explicit vector soliton solution is obtained. The explicit solution for the solitons trajectories is studied. In particular cases this solitons solution can be reduced as to the short scalar soliton solution on linear inhomogeneity profile, as to well – known Chen soliton solution.
The effect of dielectric supports on the slowing factor and dispersion of the helical line in TWT is considered. A method for the calculation of the slowing down in the helical line with the complicated configuration of the dielectric supports is proposed. A procedure for the experimental study of dispersion in the helical slow_wave system is presented. The calculated results are compared with the experimental data.
A TWT model formed by a meta-magnetic plate and a metal screen is offered and analyzed. The dispersion equation of the model in the presence of a homogeneous electron beam filling the space between the plate and the screen is derived and solved. The coupling and depression coefficients are calculated by the method of differentiation the dispersion equation. The calculated characteristics are compared with the TWT models on a dielectric plate and an “impedance” comb.
A study of waveguide structures with magnetic walls that were based on mushroom-shaped metamaterials has been carried out. We used Ansoft HFSS to simulate waveguide filters with a forbidden frequency band. The results obtained showed that a magnetic wall made of periodic various sized unit cells can provide several forbidden frequency bands instead of only one in case of single sized elements. We also demonstrated that it is possible to control rejection bands of frequency-selective surfaces by varying the permeability of ferrite coating of the metamaterial.
This volume presents new results in the study and optimization of information transmission models in telecommunication networks using different approaches, mainly based on theiries of queueing systems and queueing networks .
The paper provides a number of proposed draft operational guidelines for technology measurement and includes a number of tentative technology definitions to be used for statistical purposes, principles for identification and classification of potentially growing technology areas, suggestions on the survey strategies and indicators. These are the key components of an internationally harmonized framework for collecting and interpreting technology data that would need to be further developed through a broader consultation process. A summary of definitions of technology already available in OECD manuals and the stocktaking results are provided in the Annex section.