Исследование уплотнения спектра сигнала в нелинейных структурах квазистационарным методом
The transmission of а complex signal through nonlinear structures (semiconductor diodes, high-power transistor amplifiers, microwave vacuum amplifiers, ets.) is investigated by means of quasi-stationary method, and functional models of devices are applied. The models use the quasi-stationary method of analysis of multifrequency signal transformation. Certain properties and peculiarities that are exhibited by nonlinear devices and that induce so-called spectrum multiplexing, i.e., formation of combination components, including those observed within the basic spectrum, are considered. The possibilities of spectrum multiplexing in nonlinear elements with a polynomial quadratic, cubic, or more complicated characteristic are discussed.
Questions of efficiency increase in the field of spare parts (SP) delivery management within the limits of technical products’ after-sales service (ASS) are considered in the article. In these objectives the use of modern information technologies of functional modeling of process organization and their probabilistic analytical models for delivery planning automation on the basis of technical and economic criteria has been suggested. The urgency to solve the problems of the technical products’ after-sales service is proved and the basic risks arising during a performance of this process are identified. The version of functional model describing the process of automated delivery organization management is examined. The example illustrating the automated planning of the delivery maintenance is provided. Dynamics of operated technical products’ quantity variation is represented in the integrated graphic type, providing a way to predict dynamics of quantity variations of serviceable technical products in a constitution of the contractor both in the form of spare parts of the fixed nomenclature and in the form of the curve variation, describing an average factor of technical products’ serviceability. Application of the earned value method is proved to be an effective solution to the problem of cost management in the field of spare part deliveries. The example of automated cost management of spare part deliveries on the basis of the earned value method is considered. The qualitative analysis of risks of being behind the default delivery schedule is examined. Results are estimated by means of the technical product serviceability factor and index that shows deviation from the planned schedule of spare parts delivery. By means of the offered approach it is possible to create algorithms that allow not onlyto estimate both operated and uncontrollable risks, but also to find valid ways to prevent them. It will allow to provide comprehensible balance between the cost and quality that satisfies all current market requirements, as well as to minimize the financial risksconnected both with overestimation and underestimation of the prices on ASS of technicalproducts in comparison with veritable figures.
The possibilities of use as the output stage television transmitter traveling wave tube to amplify simultaneously several television channels. TWT has a wide bandwidth and a high gain. The simulation of the transformation of multi-frequency signals, including a lest of the television signal. The method of analysis — a quasistationary. Lamp determined by its amplitude and fazo-amplitude external characteristics. The case of sufficiently smooth characteristics that can be approximated by a polynomial of low degree. For a given bandwidth requirements for high-frequency signal and intermodulafion interference investigated for optimal arrangement of three to six TV channels in a given band TWT. We also consider the effect of the phase of each channel at the level of the Raman background. It is shown that the use of the phase shifter on the even (or odd) channels to reduce intermodulation background caused by combination up to 5 dB at the same total power. The calculations of the nonlinear interaction of the six channels, received frequency and levels of combinational components with different capacities and placement of frequency channels. We give conditions for selection of the total input power TWT in which intermodulation interference is less than the level specified by the standard.
Generalized error-locating codes are discussed. An algorithm for calculation of the upper bound of the probability of erroneous decoding for known code parameters and the input error probability is given. Based on this algorithm, an algorithm for selection of the code parameters for a specified design and input and output error probabilities is constructed. The lower bound of the probability of erroneous decoding is given. Examples of the dependence of the probability of erroneous decoding on the input error probability are given and the behavior of the obtained curves is explained.
The dynamics of a two-component Davydov-Scott (DS) soliton with a small mismatch of the initial location or velocity of the high-frequency (HF) component was investigated within the framework of the Zakharov-type system of two coupled equations for the HF and low-frequency (LF) fields. In this system, the HF field is described by the linear Schrödinger equation with the potential generated by the LF component varying in time and space. The LF component in this system is described by the Korteweg-de Vries equation with a term of quadratic influence of the HF field on the LF field. The frequency of the DS soliton`s component oscillation was found analytically using the balance equation. The perturbed DS soliton was shown to be stable. The analytical results were confirmed by numerical simulations.
Radiation conditions are described for various space regions, radiation-induced effects in spacecraft materials and equipment components are considered and information on theoretical, computational, and experimental methods for studying radiation effects are presented. The peculiarities of radiation effects on nanostructures and some problems related to modeling and radiation testing of such structures are considered.
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.