investigating space radiation
Majid Mokhtari; Hamideh Daneshvar; Morteza Bahmani nejad; Shahryar Malekie; Armin Mosayebi,; Amir Torabpoor-Isfahani,; Iman Aryanian
Volume 15, Issue 2 , June 2022, , Pages 59-69
Abstract
Sandwich panels are used in various industries due to their high special strength. It is used in ultra-light aerospace structures. In this paper the protective effect of sandwich structures used in ultralight space structures against gamma rays is investigated. Eight structures of the most widely used ...
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Sandwich panels are used in various industries due to their high special strength. It is used in ultra-light aerospace structures. In this paper the protective effect of sandwich structures used in ultralight space structures against gamma rays is investigated. Eight structures of the most widely used structures used in space structures such as telecommunication antennas and satellite bodies are exposed to radioisotopic sources of gamma rays (Amercium barium and cesium) with energies of 60 kV, 80 kV, 382 and 66 kV, have been compared to each other. Surface material (aluminum and carbon), surface thicknesses and honeycomb cell dimensions are the most important evaluation parameters. In this paper, different structures have been compared using the "special protection" parameter and the best structure from a protection perspective has been identified and reported.
Mohammad Hossein Tirandaz; Milad َAzimi
Volume 13, Issue 2 , June 2020, , Pages 37-50
Abstract
This paper aims to use H2 and H∞ norms to optimally place sensor/actuator patches on a flexible structure. Unlike most existing optimization methods, the proposed approach not only increases the norms of the controlled modes of the system but also it can reduce the system's spillover problems by ...
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This paper aims to use H2 and H∞ norms to optimally place sensor/actuator patches on a flexible structure. Unlike most existing optimization methods, the proposed approach not only increases the norms of the controlled modes of the system but also it can reduce the system's spillover problems by taking into account the residual modes and reducing systems H2 and H∞ norms. The residual vibration of the system is captured considering sandwich structures and the finite element analysis. In order to show the optimal placement effect of piezoelectric patches, the vibrational behavior of the closed-loop system is controlled using strain rate feedback controller. Numerical simulation is performed to study the debonding effects between the sandwich layers.
