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We provide a block diagram of an array element in a large-scale integrated photosignal read circuit with adaptive integration time (which, in this application, depends on the ambient light level). We propose a mathematical description of the light detection process using a focal-plane array with this type of large-scale integrated circuit. We demonstrate that if the focal-plane array transfer function is nonlinear (due to the additive integration time), this will expand the input-signal dynamic range to 130–140 dB. We conclude that a focal-plane array with a log-linear transfer function has a better signal-to-noise ratio (10%–30% higher, with low input current) than one with a logarithmic transfer function, with no degradation to the dynamic range. We provide equations to obtain the dynamic range and signal-to-noise ratio from the transfer function for a focal-plane array.

The technique of spatially resolved cross-correlation spectroscopy (CCS) is used to carry out diagnostic measurements of the barrier discharge (BD) in air at atmospheric pressure. Quantitative estimates for electric field strength E(x,t) and for relative electron density n_e(x,t)/n_e^max are derived from the experimentally determined spatio-temporal distributions of the luminosity for the spectral bands of the 0-0 transitions of the second positive system of N₂ (λ = 337.1 nm) and the first negative system of N₂⁺ (λ = 391.5 nm). These results are used to test the validity of some physical models of electrical breakdown in a BD. The influence of the spatio-temporal structure of the discharge on the chemical kinetics of ozone synthesis is studied by means of a semi-empirical method based on the results of spatially resolved CCS measurements.

The dependence of the ratio of a charge transferred inside a discharge gap and a charge transferred in an outer circuit on the width of the discharge gap was measured in a silent discharge in oxygen, air and argon under atmospheric pressure. These dependences lie below theoretical curves derived from a one-dimensional model.

Conclusions 1.The thickness of specimens when varied in the range from 0.3 cm to 3.0 cm has a marked effect on the strength of the foam plastic. The form of the relation between strength and thickness depends on whether the cross section of the specimen is kept constant, or is varied at the same time.2.The suitability of Weibull's statistical theory of strength, and of the model of the test specimen with a binomial distribution of defects, for estimating the strength of foam plastics, has been demonstrated.3.The particular character of the influence exerted by the dimensions of specimens on tensile test results must be taken into account when comparing the results of tests obtained from foam plastic specimens of different dimensions, if design of structural components containing this material is to be based on such results.

The relationships concerning the deformation of rigid cellular foams during elongation are reviewed under the conditions of a monotonous load increase. The cellular structure behavior is modelled by the operation of a certain piston structure. The proposed equation leads to a satisfactory approximation of the experimental stress-strain diagram for polystyrene and poly(vinyl chloride) foams.