Применение запредельных волноводов для пирометрических измерений
Electronic equipment of spacecraft is exposed to ionizing radiation of outer space, which is another reason for failure. Currently accepted to evaluate separately the reliability of electronic equipment and its radiation resistance, despite the fact that these phenomena are interrelated. The aim of the article is to estimate effects of ionizing radiation on the reliability of microwave devices, namely, the probability of failure-free operation of a microwave amplifier.
The probability of device failure model Q(t) for active lifetime is constructed as a product of the probabilities of failure Q1(t) - the probability of device failure due to set the total ionizing dose, Q2(t) - probability of failure of the device in the absence of exposure to ionizing radiation, Q3(t) - the probability of a single effect event. Probabilities Q2(t) and Q3(t) are valued at current normative documents. Probability Q1(t) is calculated based on probabilistic and physical models.
Research shows that, despite the high radiation resistance of microwave devices used in electronic equipment of spacecraft, when the long lifetime is required the low intensity radiation will have a tangible impact on the probability of failure. And that should be considered when designing equipment.
Methods for extension of the rejection band of microwave devices on the basis of planar modified mushroomshaped metamaterials comprising either twolayered topological structures with frequencyselec tive surfaces or multilayer bulk structures with intermediate layers containing splitring resonators are pro posed. Computer simulation of such devices, clearly demonstrating a two to sixfold extension of the rejec tion band is performed. Experimental results confirming the results of numerical simulation are presented.
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.