Метод автоматизированного синтеза систем обеспечения тепловых режимов радиоэлектронной аппаратуры
This paper presents method that allow to extend computer-aided design of radio-electronic devices and to automate choosing process of thermal regime and temperature control systems for electronic chips and entire device. That process both structural and parametrical optimization is determined as a thermal regime system synthesis. We consider various classes of on-board aerospace and mobile military devices sensitive to mass and dimension. The study proposed a new optimal design criterion of thermal regime systems and suggested mathematical expediency estimation rank for every parameter changing on every optimization step.
The article deals with forecasting the dependability indicators of state-of-the-art spacecraft onboard equipment. The authors demonstrate the applicability of the results of equipment and components testing for resistance to ionizing radiation in forecasting dependability indicators. They prove the applicability of Alfa distribution of time to failure in forecasting CMOS IC reliability and longevity. The paper presents design ratios for probability evaluation of fail-safe operation, mean time to failure and minimum operation time. Ways are shown to improve the resistance of state-of-the-art spacecraft onboard equipment through the use of specialized means of protection against the effects of ionizing radiation of the outer space. This research (No. 14-05-0038) was conducted with the support of the Higher School of Economics Academic Fund Program in 2014.
The quasi-3D BGA package thermal model is proposed. The general 3D heat transfer problem is correctly transformed to the set of 2D equations for temperature distribution in different layers of BGA package construction. It is shown that quasi-3D model provides the reasonable accuracy for standard and thermally enhanced BGAs. The software tool OVERHEAT-BGA is developed to obtain an numerical solution with considerably (6 – 10 times) reduced CPU time in comparison with universal 3D simulators.
The good agreement between designed and measured temperatures for standard and XP BGA packages is achieved.
The method of optimization of systems to ensure thermal regimes REA (TCS), which as a model of heat transfer method uses electrothermal analogy and relies on the criterion of optimal design RESEARCHER. The criteria taken into account by the ratio of costs to sell is the amount of the value of the system elements RESEARCHER, the cost of power consumption and the amount of weight applied RESEARCHER to produce effects (qualitative assessment) is the deviation of temperature on the cooled element from the set of values to ensure the required reliability.
The article discusses the thermal model of Peltier element and a heat pipe intended for inclusion in the overall thermal model design of electronic equipment to optimize system parameters to ensure its thermal regime. Models are constructed on the basis of experimental data of the manufacturer and contain the minimum number of adjustable parameters.
The article solves a problem of estimating the demand for graduates of the higher vocational training on an example of the Altay Territory by methods of optimization using modern program toolkit.
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.