Informatics, computer technology and management. Рубрика в журнале - Siberian Aerospace Journal
Using signals of navigation satellites in the monitoring of the Earth covers
Статья научная
The features and capabilities of remote sensing of earth covers by means of signals of navigation satellites are presented. The methods of reflectometry of the surfaces of earth covers and radioscopy of forest canopy are described. The options for using the signals of GLONASS, GPS systems are considered. Test measurements of interference diagrams were carried out on 5 test platforms from heterogeneous soil surfaces: salt marshes and asphalt; water surfaces of saline and freshwater bodies in summer, including ice cover of small thickness in the period of autumn freeze-up. The method of radioscopy helped obtain the data on the spatial and temporal characteristics of attenuated signals of the GLONASS and GPS satellites in the pine forest. Estimates of the linear attenuation coefficients of the signals passing through a forest canopy with a coordinate reference were made. The results obtained are the basis for the development of methods and technologies for continuous monitoring of the characteristics and state of earth covers by means of signals of navigation satellites for solving a wide range of applied tasks.
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Volume temperature control at automated high-frequency processing of polymer and composite materials
Статья научная
The purpose of this work is to develop and justify a method for volumetric temperature control of a polymer and composite material in automated high-frequency processing. The developed method is implemented by in-troducing thermocouples into the prism-shaped or cube-shaped sample body according to a certain pattern of their location throughout the volume. This technique is cost-effective and easy to implement compared to expen-sive and specialized equipment with complex design, as well as to the cost of thermocouples having a simple de-sign. Methods to achieve the purpose of the research of the contact method of volumetric temperature of a polymer or composite sample control are development and outlining thermocouples throughout the volume so as to iden-tify the most accurate temperature spectrum of the polymer or composite sample during automated high-frequency processing. Another method to achieve this purpose is the method of finding out how it will affect the measurements accuracy of the heating sample temperature from the introduction of thermocouples by making holes in it for installation. For this, a finite-difference mathematical calculation of the dependence of the sample temperature on the number of holes for thermocouples in it was performed in the MSC Patran Sinda software package. The calculation results were summarized and presented on graphic data. Further, a general mathemat-ical calculation was performed according to the formulas for the process of heat and mass conductivity calcula-tion, the results of which were table and graphic data. At the end of the finite-difference and general mathematical calculation, a comparative analysis of the ob-tained error of temperature measurement from the introduction of thermocouples into the body of the sample was performed. Based on this analysis, the developed method is applicable for further research on automated high-frequency processing of polymer and composite materials, since the errors obtained do not exceed the permissi-ble 3 %.
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