Optimization of 110 m Aperture Fully Steerable Radio Telescope Prestressed Back Frame Structure Based on a Genetic Algorithm

Radio telescopes play an important role in lunar exploration projects, manned space flight projects, and navigation systems. China is constructing a giant 110 m aperture ground-based fully steerable radio telescope in Qitai County, Xinjiang Uygur Autonomous Region. In this paper, a 110 m aperture fully steerable radio telescope prestressed back frame structure is proposed and optimized to improve the reflector accuracy and to reduce the weight of the telescope. First, prestressed cables are introduced into the back frame structure, and three innovative cable layout schemes are presented. Second, for stress state analysis, the wind pressure distribution on the main reflector is explored using wind tunnel experiments. Third, some improvements in genetic algorithms for addressing computational complexity are explained. Finally, the effects of prestressed cables on the weight reduction and reflector accuracy improvement are analysed. Additionally, in order to evaluate the safety of the prestressed back frame structure, its strength has been checked, and the internal force and displacement under static conditions and in earthquakes are interpreted in detail.

Contribution of Leningrad Enterprises and Institutions to the Preparation of the First Man’s Space Flight.

Participation of Leningrad scientists, industrial workers and representatives of other institutions of this city in creation of various components of machines and technical products which assisted in realization of historical space flight of the first manned spacecraft ―Vostok‖ with the citizen of the USSR, major Yury Alekseevich Gagarin has been analyzed in the article. Leningrad citizens – representatives of different professions and specialties, such as opticians, biophysicists, specialties of radio and telecommunication engineering, mathematicians and scientists of gas dynamics, chemistry, digital machinery and others participated in preparation of the first space flight. The author of the article mentions such Leningrad enterprises, scientific establishments and higher institutions as Leningrad metal plant, M.I. Kalinin’s plant, mathematical institute named after V.A. Steklov AS USSR, physical-technological institute named after A.F. Yoffe AS USSR, State optical institute named after S.I. Vavilov, SRI-195, now the Institute of radio navigation and time, State institute of applied chemistr y, AUSRI of Television, special design offices (OKB-448, STKB ―Biophyspribor‖). The role of Leningrad higher institutions, namely Petr Velikyi Polytechnic University, Leningrad University named after A.A. Zhdanov; Leningrad holding the Order of the Red Banner Air Force Academy named after A.F. Mozhaisky has also been emphasized in the considered processes. It has been analyzed technological innovations, technical devices and techn ological decisions of Leningrad citizens participated in preparation and reali zation of the first manned space flight. It is named those scientists and industrial workers who partic ipated in their production as well as those who were awarded State Prizes according to the results of Yu. A. Gagarin’s space flight. It has been mentioned that in definite cases necessary for the flight technics or technical devices were manufactured at the enterprises of the city and tested at the plants ground. Such specific form of Leningrad citizens’ participation in preparing the first manned space flight as the work of one of the teachers from the Air Force Academy aimed at the radio techniques training the Orenburg flight school cadets in the second half 0f 1950s has also been described in the article. Just at that time Yury Gagarin studied in this school.

What the dogs did: animal agency in the Soviet manned space flight programme

This paper examines the agency of the dogs used to develop the Soviet manned space flight programme by considering what the dogs did as experimental subjects, as dog technologies, and as individual dogs in the context of the historically conditioned practices of Soviet science. Looking at how Soviet space researchers refined Pavlovian behaviourism and integrated it into a complex engineering project helps clarify the conditions under which the dogs worked and the assumptions that guided the human researchers. The paper uses theoretical perspectives that contextualize animal agency in terms of relationships and then looks at those relationships from an ethological perspective. This provides a sense of what the dogs did that distinguishes between how humans understand dogs and what we know about dogs’ cognitive and social capacities. The paper proposes a model of animal agency that looks seriously at the dogs’ relationships with human researchers and suggests that the dogs’ significance as historical subjects depends as much on what they did as dogs as it does on how their contributions to the space race were perceived.