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This article is the first in a continuing series of articles begun by the editors in the previous issue of the journal and dedicated to the Fiftieth Anniversary of the Measurement Engineering and Metrology Branch of the Central Aerohydrodynamics Institute. The authors describe singleboard measuring instruments designed to be used in conjunction with IBM personal computers in the construction of measurement and monitoring systems for industry and scientific research. Specific aspects of their structure and the feasibility of using the instruments in combination with sensors of physical quantities for the solution of problems of experimental aerodynamics are discussed.

We report on the development of instruments for measuring pressures on the surface of drained aircraft models in wind tunnels at TsAGI. As sensors we used ESP-48 electronic pressure commutators manufactured by PSI (USA).

For manifolds Mn, n ≥ 6, with free abelian fundamental group and four-connected universal covering, the author proves the sharpness of Novikov's inequalities for rational cohomology classes ξH1(M, Q) belonging to an open everywhere dense set UH1(M, R). Figures: 1. Bibliography: 20 titles.

A classification theorem is proved for certain types of generalized cohomology theories. The necessary technical apparatus (stable Postnikov systems and their multiplicative properties) is developed, and with its help a complete classification of spectra with coefficient ring Fp[t], and others, is carried out.Bibliography: 8 titles.

The following theorem (a conjecture of Rourke) is proved: every commutative ring spectrum of characteristic 2 which has finite type is isomorphic to the spectrum of ordinary cohomology theory with coefficients in .Bibliography: 13 titles.